The Curator · Free Tools
278 FREE Tools!
Useful, honest utilities for everyday work — PDFs, images, writing, money and code. Every tool is 100% free, needs no account, and runs entirely inside your browser, so your files and words never leave your device.
Word Counter
Count words, characters, sentences and reading time as you type.
Open tool →Text Compare (Diff Checker)
Compare two texts line by line and highlight what changed.
Open tool →Percentage Calculator
Work out X% of Y, what percent X is of Y, and percentage change.
Open tool →Mortgage Calculator
Estimate monthly mortgage payments, total interest and payoff cost.
Open tool →Compound Interest Calculator
See how savings grow with compounding and monthly contributions.
Open tool →Hourly to Salary Calculator
Convert hourly pay to weekly, monthly and annual salary — and back.
Open tool →JSON Formatter & Validator
Pretty-print, minify and validate JSON with clear error messages.
Open tool →Strong Password Generator
Create strong random passwords with your choice of characters.
Open tool →Image Compressor
Shrink JPG, PNG and WebP file sizes without uploading.
Open tool →Image Resizer
Resize images to exact pixel dimensions or a percentage.
Open tool →WebP to JPG Converter
Convert WebP images to JPG so they open everywhere.
Open tool →QR Code Generator
Make free QR codes for links, text, Wi-Fi and contacts — no sign-up, no expiry.
Open tool →Merge PDF
Combine several PDFs into one file, in the order you choose.
Open tool →Split PDF
Extract a page range from a PDF into a new file.
Open tool →JPG to PDF Converter
Turn one or more photos or scans into a single PDF.
Open tool →Rotate PDF
Turn sideways or upside-down PDF pages the right way up — all pages or just some.
Open tool →Favicon Generator
Create favicon and app-icon PNGs in every standard size from one logo.
Open tool →Sales Tax & VAT Calculator
Add tax to a price, or work out the tax inside a tax-inclusive price.
Open tool →Unix Timestamp Converter
Convert epoch timestamps to dates and dates to timestamps.
Open tool →CSV to JSON Converter
Turn spreadsheet CSV into a JSON array of objects.
Open tool →BMI Calculator
Body mass index in metric or imperial, with WHO categories.
Open tool →Days Between Dates Calculator
Count days, weeks and weekdays between two dates.
Open tool →PDF to JPG Converter
Turn every page of a PDF into a sharp JPG image.
Open tool →PDF to Text Extractor
Pull the plain text out of a PDF to copy, edit or search.
Open tool →HEIC to JPG Converter
Convert iPhone HEIC photos to JPG that open everywhere.
Open tool →Crop Image
Crop photos to square, 16:9, 4:3, portrait or any exact pixel size.
Open tool →Password Strength Checker
Estimate how hard a password is to guess — privately.
Open tool →Fuel Cost Calculator
Estimate the fuel cost of a road trip and split it between passengers.
Open tool →Online Stopwatch & Countdown Timer
A precise stopwatch with laps, and a countdown timer with an alarm.
Open tool →Cooking Measurement Converter
Convert cups, tablespoons, teaspoons, millilitres and fluid ounces.
Open tool →Time Zone Converter
Convert a meeting time between cities, with daylight saving handled.
Open tool →Weekly Time Card Calculator
Add up a week's shifts, breaks and overtime pay.
Open tool →Credit Card Payoff Calculator
How long to clear a card balance, and how much interest it costs.
Open tool →Colour Contrast Checker (WCAG)
Check text and background colours against WCAG AA and AAA.
Open tool →Cron Expression Explainer
Check a cron schedule and see its next five run times.
Open tool →IP Subnet Calculator (IPv4 CIDR)
Network, broadcast, mask, wildcard and usable host range for any CIDR.
Open tool →Random List Picker & Shuffler
Pick fair random winners from a list or shuffle it.
Open tool →Fraction Calculator
Add, subtract, multiply and divide fractions and mixed numbers.
Open tool →Electricity Cost Calculator
What an appliance costs to run per day, month and year.
Open tool →Readability Score Checker
Flesch Reading Ease and grade level for any paragraph.
Open tool →Loan Amortization Schedule
Month-by-month table of interest, principal and balance.
Open tool →Freelance Hourly Rate Calculator
The minimum rate you need to hit your income goal.
Open tool →Pomodoro Timer
Focus in 25-minute sprints with automatic breaks.
Open tool →Running Pace Calculator
Pace per km and mile, speed and race-time predictions.
Open tool →CSS Gradient Generator
Design linear and radial gradients and copy the CSS.
Open tool →FIRE Number Calculator
How much you need to retire early, and when you'll get there.
Open tool →Calories Burned Calculator
Estimate calories for walking, running, cycling and more.
Open tool →SVG to PNG Converter
Convert SVG files or code to crisp PNG at any scale.
Open tool →VAT / GST Calculator
Add or remove VAT and GST at any rate.
Open tool →Typing Speed Test
Measure your words per minute and accuracy.
Open tool →Reorder PDF Pages
Rearrange, drop or duplicate pages in a PDF.
Open tool →Emoji Picker & Copy
Search hundreds of emoji and copy them with one click.
Open tool →Text to Speech Reader
Have any text read aloud with your browser's voices.
Open tool →Debt Snowball vs Avalanche
Compare the two classic debt payoff strategies.
Open tool →Meme Generator
Add classic top and bottom caption text to any image.
Open tool →List to Comma-Separated Converter
Convert a column of lines into a comma, semicolon or custom-separated list.
Open tool →JSON to TypeScript Interface
Generate TypeScript interfaces from a sample JSON payload.
Open tool →Retirement Savings Calculator
Project your retirement balance from savings, contributions and growth.
Open tool →Military Time Converter
Convert between 12-hour AM/PM time and 24-hour military time.
Open tool →Bold Text Generator
Turn letters and numbers into bold Unicode text you can paste anywhere.
Open tool →XML Formatter & Validator
Pretty-print XML with clean indentation and catch mismatched tags.
Open tool →Future & Present Value Calculator
See what savings grow to, and what a future sum is worth today.
Open tool →Business Days Calculator
Count working days between dates, or add business days to a date, skipping holidays.
Open tool →NPV & IRR Calculator
Find the net present value and internal rate of return of any cash flows.
Open tool →Concrete Calculator
Work out cubic yards and bags of concrete for a slab or patio.
Open tool →Mortgage Extra Payment Calculator
See how much time and interest extra monthly payments save.
Open tool →Case Converter
Switch text to UPPER, lower, Title, Sentence, camelCase and more.
Open tool →Remove Duplicate Lines
Delete repeated lines from lists, exports and logs — keep the first.
Open tool →URL Slug Generator
Turn any title into a clean, SEO-friendly URL slug.
Open tool →Lorem Ipsum Generator
Generate placeholder paragraphs, sentences or words for designs.
Open tool →Loan Calculator
Monthly payment and total interest for personal, car or student loans.
Open tool →ROI Calculator
Return on investment, profit and annualised ROI in one place.
Open tool →Profit Margin Calculator
Gross margin, markup and profit from cost and selling price.
Open tool →Discount Calculator
Sale price and savings from any percentage off — including stacked deals.
Open tool →Tip Calculator
Tip amount and split the bill evenly between any number of people.
Open tool →Base64 Encode / Decode
Encode text to Base64 or decode Base64 back to readable text.
Open tool →URL Encode / Decode
Percent-encode text for URLs or decode %20-style strings.
Open tool →Hash Generator (SHA-256, SHA-1, SHA-512)
Create SHA-1, SHA-256, SHA-384 and SHA-512 hashes of any text.
Open tool →UUID Generator
Generate random version-4 UUIDs in bulk.
Open tool →JWT Decoder
Decode a JSON Web Token's header and payload and read its expiry.
Open tool →Regex Tester
Test JavaScript regular expressions with live match highlighting.
Open tool →Color Converter (HEX, RGB, HSL)
Convert colours between HEX, RGB and HSL with a live preview.
Open tool →PNG to JPG Converter
Convert PNG images to smaller JPG files, with a background colour for transparency.
Open tool →JPG to PNG Converter
Convert JPG photos to lossless PNG files.
Open tool →Age Calculator
Exact age in years, months and days — plus days until the next birthday.
Open tool →Delete PDF Pages
Remove blank, duplicate or private pages from a PDF before you share it.
Open tool →Add Page Numbers to PDF
Stamp clean page numbers onto every page of a PDF.
Open tool →Watermark PDF
Add a diagonal DRAFT or CONFIDENTIAL watermark across every page.
Open tool →Rotate & Flip Image
Rotate photos 90° at a time and mirror them horizontally or vertically.
Open tool →Black & White / Sepia Image Filter
Turn a photo black and white, sepia or inverted in one click.
Open tool →Image to Base64 Converter
Turn an image into a Base64 data URI for HTML, CSS or JSON.
Open tool →Image Colour Picker
Click any pixel in a photo to get its exact HEX and RGB colour.
Open tool →Sort Lines Alphabetically
Sort a list A→Z, Z→A, by length, or shuffle it randomly.
Open tool →Find and Replace Text
Replace every occurrence of a word or pattern — with optional regex.
Open tool →Remove Extra Spaces
Collapse double spaces, trim lines and remove extra blank lines.
Open tool →Reverse Text
Reverse characters, word order or line order.
Open tool →Add Line Numbers
Number each line of text, with your own start and separator.
Open tool →Markup Calculator
Turn a cost and markup into a selling price — and see the real margin.
Open tool →Break-Even Calculator
Find how many units you must sell to cover your fixed costs.
Open tool →CAGR Calculator
Compound annual growth rate between a start and end value.
Open tool →Savings Goal Calculator
How much to save each month to reach a goal by a date.
Open tool →Inflation Calculator
See how inflation changes prices and buying power over time.
Open tool →Binary, Hex & Decimal Converter
Convert numbers between binary, octal, decimal and hexadecimal.
Open tool →HTML Entity Encoder / Decoder
Escape < > & " ' for HTML, or decode entities back to text.
Open tool →JSON to CSV Converter
Flatten a JSON array into a CSV you can open in a spreadsheet.
Open tool →Add Days to a Date
Find the date a number of days or weekdays from today.
Open tool →Length Converter
Convert mm, cm, metres, km, inches, feet, yards and miles.
Open tool →Weight Converter
Convert grams, kilograms, tonnes, ounces, pounds and stone.
Open tool →Temperature Converter
Convert Celsius, Fahrenheit and Kelvin instantly.
Open tool →Random Number Generator
Pick fair random numbers in any range — with or without repeats.
Open tool →QR Code Scanner from Image
Read a QR code from a photo or screenshot — no camera app needed.
Open tool →JPG & PNG to WebP Converter
Convert images to WebP for faster websites — see the size saved.
Open tool →Word Frequency Counter
See which words you use most — great for editing and keyword checks.
Open tool →Text to Binary Converter
Convert text to 8-bit binary code and back again.
Open tool →Morse Code Translator
Translate text to Morse code and back — and hear it played.
Open tool →Roman Numeral Converter
Convert numbers to Roman numerals and back (1–3999).
Open tool →Unit Price Comparison Calculator
Which pack is really cheaper? Compare price per gram, ml or item.
Open tool →Pay Raise Calculator
See a raise as a percentage, a new salary and a real, after-inflation figure.
Open tool →Speed, Distance & Time Calculator
Solve for speed, distance or travel time from the other two.
Open tool →Area Converter
Convert square metres, hectares, acres, square feet and more.
Open tool →Volume Converter
Litres, millilitres, US and UK gallons, pints, fluid ounces and cubic feet.
Open tool →Speed Converter
Convert km/h, mph, metres per second, knots and feet per second.
Open tool →Data Storage Converter (KB, MB, GB, TB)
Convert bytes, KB, MB, GB, TB and their 1024-based KiB, MiB, GiB cousins.
Open tool →Week Number Calculator
Find the ISO-8601 week number of any date.
Open tool →What Day of the Week Was It?
Find the weekday of any date — past or future — plus day of the year.
Open tool →Countdown to a Date
A live countdown in days, hours, minutes and seconds to any moment.
Open tool →Hours & Minutes Calculator
Add and subtract times like 1:45 + 2:30 − 0:15.
Open tool →BMR & Daily Calorie Calculator
Estimate calories burned at rest and to maintain your weight.
Open tool →Simple Interest Calculator
Interest on a principal at a flat rate — no compounding.
Open tool →Split the Bill Calculator
Split a restaurant bill with tip evenly between friends.
Open tool →URL Parser & Query String Viewer
Break a URL into protocol, host, path, hash and decoded parameters.
Open tool →PX to REM Converter
Convert CSS pixels to rem and back, with a quick reference table.
Open tool →Chmod Permissions Calculator
Convert Unix file permissions between checkboxes, octal and rwx.
Open tool →Number to Words Converter
Write numbers out in English words — for cheques, contracts and invoices.
Open tool →JSON to YAML Converter
Turn JSON into clean, readable YAML for configs and pipelines.
Open tool →HTML to Plain Text
Strip tags from HTML and keep readable text, lines and bullets.
Open tool →Markdown Table Generator
Convert CSV or pasted spreadsheet cells into a Markdown table.
Open tool →JSON String Escape / Unescape
Escape quotes, newlines and tabs for JSON strings — or reverse it.
Open tool →Query String ↔ JSON Converter
Read URL parameters as JSON, or build a query string from JSON.
Open tool →Caesar Cipher & ROT13
Shift letters to encode or decode Caesar and ROT13 messages.
Open tool →Dice Roller (d4 to d100)
Roll any dice with standard notation like 3d6+2, or flip a coin.
Open tool →GCD & LCM Calculator
Greatest common divisor and least common multiple of any list of numbers.
Open tool →Prime Number Checker & Factorization
Check if a number is prime and break it into prime factors.
Open tool →Mean, Median, Mode & Standard Deviation
Descriptive statistics for any list of numbers.
Open tool →GPA Calculator
Credit-weighted grade point average on the 4.0 scale.
Open tool →Sleep Cycle Calculator
Best bedtimes or wake-up times based on 90-minute sleep cycles.
Open tool →Pregnancy Due Date Calculator
Estimate a due date from the last period, adjusted for cycle length.
Open tool →Aspect Ratio Calculator
Find an image or video ratio and resize without distortion.
Open tool →Scientific Notation Converter
Convert numbers to and from scientific and E notation.
Open tool →Remove Line Breaks
Fix text copied from PDFs and emails with broken lines.
Open tool →Email & Link Extractor
Pull every email address and web link out of any text.
Open tool →Word Wrap Tool
Wrap text to a fixed line length without splitting words.
Open tool →UTF-8 Byte Counter
Count bytes, characters and code points in any string.
Open tool →Card Number Checksum (Luhn) Validator
Check a card or ID number's Luhn checksum and network.
Open tool →ISBN Validator & Converter
Validate ISBN-10/13 check digits and convert between them.
Open tool →HTTP Status Code Lookup
Searchable list of HTTP status codes in plain English.
Open tool →Rule of 72 Calculator
How many years it takes money (or prices) to double.
Open tool →Commission Calculator
Sales commission with optional quota and base pay.
Open tool →Net Worth Calculator
Add up what you own and owe to see your net worth.
Open tool →Online Tally Counter
Click or press a key to count anything.
Open tool →Coin Flip
Fair heads-or-tails with running statistics.
Open tool →Body Fat Calculator (US Navy Method)
Estimate body fat percentage from a tape measure.
Open tool →Leap Year Checker
Is a year a leap year? Plus the next leap years.
Open tool →Placeholder Image Generator
Make sized placeholder images for mockups and layouts.
Open tool →Anagram Checker
Check whether two words or phrases are anagrams.
Open tool →Palindrome Checker
Does it read the same backwards? Check any phrase.
Open tool →Text Repeater
Repeat a word or line up to 10,000 times.
Open tool →NATO Phonetic Alphabet Converter
Spell text as Alfa, Bravo, Charlie — and back again.
Open tool →CSS Box Shadow Generator
Tune offsets, blur, spread and colour with a live preview.
Open tool →Character Code Converter
Text to Unicode/ASCII codes and back.
Open tool →Regex Escape Tool
Escape special characters so text matches literally.
Open tool →Dividend Yield Calculator
Yield, annual income and monthly average from dividends.
Open tool →Emergency Fund Calculator
How big your safety net should be and how long to build it.
Open tool →Debt-to-Income Ratio Calculator
The ratio lenders check before approving a loan.
Open tool →Water Intake Calculator
A daily fluid target based on weight and exercise.
Open tool →Random Team Generator
Split a list of names into fair, random teams.
Open tool →Reaction Time Test
Click when it turns green — measure your reflexes.
Open tool →Birthday Countdown
Days until your next birthday and the age you'll turn.
Open tool →Invert Image Colours
Make a negative of any photo or image instantly.
Open tool →PDF Metadata Viewer & Editor
See and change a PDF's title, author and keywords.
Open tool →Upside Down Text Generator
Flip text upside down for posts, bios and messages.
Open tool →Strikethrough & Underline Text
Cross out or underline text anywhere — no formatting needed.
Open tool →Acronym Generator
Turn a phrase into its initials, with or without small words.
Open tool →Word Scrambler
Jumble the middle letters of every word.
Open tool →HMAC Generator
HMAC-SHA1/256/384/512 signatures in hex and Base64.
Open tool →Base32 Encoder / Decoder
Encode and decode RFC 4648 Base32 text.
Open tool →Random String Generator
Secure random strings for IDs, tokens and test data.
Open tool →MIME Type Lookup
Find the Content-Type for any file extension.
Open tool →Rent Affordability Calculator
How much rent you can afford by three common rules.
Open tool →Cost per Use Calculator
Compare two purchases by what each use really costs.
Open tool →Investment Fee Calculator
See how much a 1% fee costs you over decades.
Open tool →Dog Age Calculator
Your dog's age in human years — science-based.
Open tool →Moon Phase Calculator
Moon phase, illumination and next full and new moons.
Open tool →Screen PPI Calculator
Pixel density, dot pitch and screen dimensions.
Open tool →Ovulation & Fertile Window Calculator
Estimate ovulation, fertile days and next period.
Open tool →Round Image Corners
Give any image rounded corners or a circle crop.
Open tool →Add Border to Image
Add a solid border or frame in any colour.
Open tool →Smart Quotes Converter
Switch between straight and curly typographic quotes.
Open tool →Remove Emojis from Text
Strip emoji and pictographs from any text in one click.
Open tool →Invisible Character Finder
Reveal hidden zero-width spaces, BOMs and odd whitespace.
Open tool →CSS Unit Converter
Convert px, rem, em, pt, % and vw with your own base size.
Open tool →robots.txt Generator
Build a valid robots.txt with allow and disallow rules.
Open tool →Meta Tag & Open Graph Generator
Generate SEO and social meta tags for any page.
Open tool →CSS Minifier & Beautifier
Compress CSS for production or reformat it for reading.
Open tool →CSS Color Names Reference
All 140+ named CSS colours, searchable, with HEX and RGB.
Open tool →Currency Converter (Manual Rate)
Convert between currencies using a rate you control.
Open tool →Overtime Pay Calculator
Weekly pay with overtime at time-and-a-half or any rate.
Open tool →Subscription Cost Calculator
Add up what all your subscriptions really cost per year.
Open tool →Ideal Weight Calculator
Four published formulas plus the healthy BMI range.
Open tool →Chinese Zodiac Calculator
Find your Chinese zodiac animal and element.
Open tool →Sunrise & Sunset Calculator
Sunrise, sunset and day length for any place and date.
Open tool →Habit Streak Calculator
How long is your streak — and when will you hit milestones?
Open tool →Image Pixelator
Pixelate a whole image for a retro or censored look.
Open tool →Pig Latin Translator
Turn any sentence into playful Pig Latin, capitals and punctuation kept.
Open tool →Vowel & Consonant Counter
Count vowels, consonants, digits, spaces and punctuation in any text.
Open tool →Remove Punctuation
Strip punctuation marks from text, optionally keeping apostrophes.
Open tool →Basic Auth Header Generator
Build an HTTP Basic Authorization header from a username and password.
Open tool →User Agent Parser
Decode a user agent string into browser, version, OS and device type.
Open tool →JavaScript Key Code Finder
Press any key to see its event key, code, keyCode and modifiers.
Open tool →50/30/20 Budget Calculator
Split your take-home pay into needs, wants and savings.
Open tool →Price per Square Foot Calculator
Compare property or flooring prices per square foot and square metre.
Open tool →Loan-to-Value (LTV) Calculator
Work out your LTV ratio, equity and whether mortgage insurance may apply.
Open tool →Fuel Economy Converter
Convert MPG (US & UK), L/100 km and km/L.
Open tool →Heart Rate Zone Calculator
Find your five training zones from age and optional resting heart rate.
Open tool →Test Grade Calculator
Turn a score into a percentage and letter grade, with a full grading chart.
Open tool →Online Metronome
A precise browser metronome with tempo, beats per bar and accent.
Open tool →Image to ASCII Art
Convert any photo into text-based ASCII art you can copy.
Open tool →Image Color Palette Extractor
Pull the dominant colors out of any image as HEX and RGB.
Open tool →Text to PDF
Turn plain text into a clean, paginated PDF document.
Open tool →Hashtag Generator
Turn a post description into a clean, de-duplicated list of hashtags.
Open tool →Duplicate Word Finder
Spot accidental doubled words and overused words in your writing.
Open tool →Character Limit Checker
Check your text against X, SMS, SEO title, meta description and other limits.
Open tool →.htaccess Redirect Generator
Convert a list of old and new URLs into Apache 301 or 302 redirect rules.
Open tool →Semantic Version Comparator
Compare and sort semantic versions, including pre-releases like 1.0.0-rc.1.
Open tool →CSS clamp() Generator
Create fluid font sizes that scale smoothly between two screen widths.
Open tool →APY Calculator (APR to APY)
Convert a nominal APR into the effective annual yield (APY).
Open tool →Stock Average Cost Calculator
Work out your average price per share across several purchases.
Open tool →Car Depreciation Calculator
Estimate what a car will be worth each year using a yearly depreciation rate.
Open tool →Tire Size Calculator
Decode tire sizes like 225/45R17 and compare diameter and speedometer error.
Open tool →Paint Calculator
Estimate how many gallons of paint you need for a room's walls.
Open tool →Wind Chill Calculator
Find the “feels like” temperature from air temperature and wind speed.
Open tool →Blur Image
Apply a smooth blur to any photo and download it as PNG.
Open tool →Sepia Image Filter
Give photos a warm vintage sepia tone with adjustable strength.
Open tool →Image Brightness & Contrast
Brighten dark photos and boost or soften contrast, then download.
Open tool →PDF Page Size Checker
See every page's size in inches and millimetres, and spot Letter vs A4.
Open tool →Italic Text Generator
Turn letters into italic Unicode text that keeps its slant when pasted.
Open tool →Alternating Case Text Generator
Create aLtErNaTiNg CaSe text for jokes, memes and playful captions.
Open tool →Unicode Escape Converter
Convert text to \uXXXX escapes and back for JSON, Java and JavaScript.
Open tool →SQL IN Clause Generator
Turn a pasted list into a safe, quoted SQL IN (...) clause.
Open tool →Payback Period Calculator
See how many years it takes for an investment to pay for itself.
Open tool →Weighted Average Calculator
Average values where some count more than others, like grades or prices.
Open tool →Percent Error Calculator
Compare a measured value with the true value as a percentage error.
Open tool →Quadratic Equation Solver
Solve ax² + bx + c = 0 with real or complex roots.
Open tool →Ratio Calculator
Simplify ratios and solve A : B = C : ? for scaling and recipes.
Open tool →Steps to Distance Converter
Convert step counts to kilometres and miles using your stride.
Open tool →Black & White Image Threshold
Turn a photo into pure black and white using a brightness threshold.
Open tool →Sharpen Image
Make slightly soft photos look crisper with adjustable sharpening.
Open tool →Small Caps Text Generator
Convert lowercase letters into ꜱᴍᴀʟʟ ᴄᴀᴘꜱ Unicode you can paste anywhere.
Open tool →Remove Numbers from Text
Strip every digit out of text and tidy the leftover spaces.
Open tool →Add Prefix & Suffix to Lines
Add the same text to the start or end of every line at once.
Open tool →Words to Number Converter
Turn English number words like “two thousand and five” into digits.
Open tool →.env to JSON Converter
Parse a .env file into clean JSON with quotes and comments handled.
Open tool →UUID Validator & Inspector
Check if a UUID/GUID is valid and see its version and variant.
Open tool →Color Shades & Tints Generator
Generate 9 tints and 9 shades of any hex colour for design systems.
Open tool →Car Lease Calculator
Estimate a monthly lease payment from price, residual and money factor.
Open tool →Savings Rate Calculator
Find what percentage of your take-home pay you save each month.
Open tool →Paycheck Frequency Converter
Convert pay between weekly, biweekly, semimonthly, monthly and yearly.
Open tool →Circle Calculator
Get radius, diameter, circumference and area from any one value.
Open tool →Triangle Calculator (3 sides)
Find area, perimeter, angles and type of a triangle from three sides.
Open tool →Pythagorean Theorem Calculator
Solve a² + b² = c² for any missing side of a right triangle.
Open tool →Square & Nth Root Calculator
Calculate square roots, cube roots and any nth root.
Open tool →Dew Point Calculator
Find the dew point from temperature and relative humidity.
Open tool →Heat Index Calculator
Calculate the “feels like” temperature from heat and humidity.
Open tool →Pressure Converter
Convert between psi, bar, kPa, atm, mmHg, inHg and more.
Open tool →Energy Converter
Convert joules, calories, kWh, BTU, eV and foot-pounds.
Open tool →Angle Converter
Convert degrees, radians, gradians, arcminutes, arcseconds and turns.
Open tool →Posterize Image
Reduce an image to a few colour levels for a bold poster look.
Open tool →Image Dimensions Checker
See an image's width, height, aspect ratio, megapixels and file size.
Open tool →Showing 9 of 278 tools
Why these tools are different
Most "free" tool sites ask you to upload your file to their servers, then show you a watermark, a queue or a paywall. Ours work the other way round: the code comes to your device, and your document stays put. You can switch your internet off after a page loads and most tools will still work.
Every tool page also includes a plain-English guide written by The Curator team — what the tool does, the formula or method behind it, its limits, and answers to common questions — so you understand the result, not just receive it.
PDF tools
PDF is the closest thing the internet has to digital paper. A PDF file describes every page as a fixed canvas, which is why it looks the same on a phone, a laptop and a printer. That fixed layout is also why PDFs are awkward to edit: the format was designed to preserve a page, not to rearrange it.
Image tools
Most image problems come down to three things: the format (JPG, PNG, WebP), the pixel dimensions, and the compression level. JPG is great for photos because it discards detail the eye barely notices. PNG is lossless and supports transparency, which makes it ideal for logos, screenshots and diagrams. WebP is a newer format from Google that is usually smaller than both, but some older apps still refuse to open it.
Text & writing tools
Writers, students, marketers and developers spend a surprising amount of time doing mechanical things to text: counting words for a brief, fixing an accidental caps-lock paragraph, removing duplicate lines from an export, or spotting what changed between two drafts. None of these tasks need artificial intelligence — they need a precise, predictable tool.
Money & business tools
Financial calculators are only useful if you understand the formula behind them. Each calculator on this page shows its working: the inputs it uses, the standard formula it applies, and what the result does and does not include. A mortgage figure that ignores property tax, or an ROI that ignores time, can be technically correct and still misleading.
Developer tools
Developer utilities are some of the most-searched tools online because everyone who touches code needs them, and they are usually needed right now: a minified API response to read, a Base64 string to decode, a token to inspect, a regular expression to debug. The risk with many online versions is that you paste secrets — API keys, tokens, customer data — into a server you know nothing about.
Everyday tools
Some questions come up again and again: how old is someone exactly, how many days until a deadline, what day of the week was a date. They are easy to get slightly wrong by hand because months have different lengths and leap years move the goalposts.
Free means free: no sign-up, no limits, no watermarks. The site is supported by advertising on these guide pages. Spotted a bug or want a tool added? Tell us.