All tools
192 free tools, grouped by category.
Developer Tools
AI Token CounterExact OpenAI token counts plus estimates for other models.Base64 Encoder/DecoderConvert text to and from Base64, including URL-safe Base64.CSS MinifierCompress CSS with csso or format it with clean indentation.curl ConverterTurn a curl command into fetch, axios, Python, Go, PHP or HTTPie code.Docker Run to ComposeTurn one or more docker run commands into a compose.yaml file.HTML Entity Encoder/DecoderEscape and unescape HTML entities, named and numeric.HTML FormatterIndent HTML neatly or shrink it with a safe minifier.HTML to MarkdownTurn HTML into clean, readable Markdown.HTTP Status CodesLook up what any HTTP status code means.JavaScript MinifierShrink JavaScript with Terser or format it for reading.JSON FormatterBeautify, minify and validate JSON with exact error locations.JSON Schema ValidatorCheck JSON against a schema and list every error clearly.JSON to GoTurn a JSON sample into Go structs with json tags.JSON to PythonTurn a JSON sample into Python dataclasses, Pydantic models or TypedDicts.JSON to TypeScriptTurn a JSON sample into ready to use TypeScript interfaces.JSON to ZodTurn a JSON sample into Zod schemas with inferred TypeScript types.JSONPath TesterTry JSONPath queries on JSON and see what they match.JWT DecoderRead a JWT's header, claims and expiry without sending it anywhere.Magic DecoderIdentify and decode an unknown string, with the most likely format first.Markdown PreviewerPreview Markdown live and convert it to clean, safe HTML.Number Base ConverterConvert numbers between binary, octal, decimal, hex and bases up to 36.Regex TesterTry a regex on sample text and see every match and group.SQL FormatterBeautify or minify SQL queries for many database dialects.String EscaperEscape and unescape strings for code, regex, CSV, SQL and shell.Text Diff CheckerSpot the differences between two texts, line by line.Unicode Character InspectorInspect code points, bytes and escapes, and find hidden characters.URL Encoder/DecoderPercent-encode and decode URLs and query string values.URL ParserBreak a URL into its parts and edit its query parameters.
Text & Writing
Add Prefix and Suffix to LinesPrefix, suffix, number, quote and join lines of text.AI Text CleanerStrip hidden Unicode, em dashes and markdown from AI-written text.Case ConverterSwitch text between upper, lower, title, camel, snake and more.Character CounterCharacter, byte and SMS segment counts with social media limits.Citation GeneratorFormat references in APA, MLA, Chicago and Harvard styles.Fancy Text GeneratorCopy and paste bold, cursive, gothic and other Unicode text styles.Find and ReplaceReplace text in bulk, with whole-word and regex support.Morse Code TranslatorConvert text to and from Morse code and play it as sound.NATO Phonetic Alphabet TranslatorSpell text as Alfa Bravo Charlie, or decode it back to letters.Readability CheckerReadability scores plus highlights for long sentences and passive voice.Remove Duplicate LinesStrip repeated lines and keep the first of each.Remove Empty LinesDelete blank lines or squeeze them down to one.Reverse TextWrite text backwards, or flip word or line order.Sort LinesSort, reverse or shuffle lines, with optional de-duplication.Text CleanerStrip HTML, straighten quotes, remove emoji and normalise text.Text to BinaryConvert text to binary or hex bytes and back.Whitespace RemoverTrim, collapse and strip spaces, tabs and line breaks.Word CounterCount words, characters, sentences and reading time.Word Frequency CounterRank every word and phrase by how often it appears.
Calculators
Average CalculatorMean, median, mode, standard deviation and more from a list of numbers.Bill SplitterItemised restaurant bills and group trip expenses, settled to the cent.BMI CalculatorAdult BMI with WHO category, in kg/cm or lb/ft/in.Body Fat CalculatorBody fat % from tape measurements, with ACE category.Break-Even CalculatorBreak-even units and revenue from fixed and variable costs.CAGR CalculatorCompound annual growth rate, future value and time to a target.Calorie and TDEE CalculatorBMR, maintenance calories and targets to lose or gain weight.Compound Interest CalculatorGrowth with compounding and monthly deposits, year by year.Credit Card Payoff CalculatorMonths to pay off a card, or the payment to clear it in time.Debt Payoff CalculatorSnowball vs avalanche: payoff time, interest and order.Discount CalculatorSale price, savings and the true total of stacked discounts.Final Grade CalculatorScore needed on the final, plus weighted grade averages.Fraction CalculatorFraction and mixed-number arithmetic with simplified answers and working.Freelance Hourly Rate CalculatorThe hourly and day rate that pays your target income.Fuel Cost CalculatorFuel needed and trip cost in any unit, split between passengers.GPA CalculatorSemester and cumulative GPA from letter grades and credits.Inflation CalculatorFuture cost, today's value and the rule of 72 at an inflation rate you choose.Loan CalculatorMonthly repayment, total interest and an amortisation schedule.Meeting Cost CalculatorTotal, hourly and per-minute meeting cost, plus a live ticking meter.Mortgage Affordability CalculatorMax home price and monthly payment from income and DTI limits.Percentage CalculatorPercent of, percent change, and increase or decrease by a percent.Profit Margin CalculatorMargin vs markup from cost and price, or the price for a target margin.Ratio CalculatorSimplify, solve, scale and split ratios.Rent vs Buy CalculatorNet worth from renting vs buying, year by year, and when buying wins.Retirement CalculatorProjected retirement pot and the monthly income it could pay.ROI CalculatorTotal and annualised return on investment.Roman Numeral ConverterNumbers to Roman numerals and back, with validation and a breakdown.Salary to Hourly CalculatorHourly, weekly, monthly and annual pay from any one of them.Savings Goal CalculatorMonthly deposit needed for a goal, or how long your savings will take.Scientific CalculatorTrig, logs, powers, roots and factorials with history.Subscription Cost CalculatorMonthly and yearly subscription totals, cost per use and savings from cancelling.Tip CalculatorTip, total and each person's share, with optional rounding up.Unit ConverterMetric, imperial and US units across 11 kinds of measurement.VAT CalculatorAdd or remove VAT/GST at any rate and see net, tax and gross.
Web & SEO
Htaccess Redirect GeneratorWrite Apache and Nginx 301/302 redirect rules without regex mistakes.Link Preview SimulatorSee how a link will look when shared, and which meta tags to fix.Meta Tag CheckerAudit a URL's SEO and social meta tags with a preview.Meta Tag GeneratorCreate title, description, canonical, Open Graph and Twitter card tags.MIME Type LookupLook up MIME types by extension and detect file types from magic bytes.Robots.txt GeneratorBuild a robots.txt file and test which URLs crawlers may fetch.Robots.txt TesterTest a URL against robots.txt rules for any crawler.Schema Markup GeneratorFill in a form and get valid, safely escaped JSON-LD schema markup.Sitemap CheckerValidate a sitemap or sitemap index and count its URLs.Slug GeneratorTurn titles and headings into clean, readable URL slugs.User Agent ParserDecode a user agent string into browser, OS, device and bot details.UTM BuilderAdd UTM campaign tags to links, or split them out of existing URLs.XML Sitemap GeneratorBuild sitemap.xml from a list of URLs, or validate an existing sitemap.
Security & Privacy
Bcrypt GeneratorCreate and verify bcrypt password hashes, and see what is inside one.Credit Card ValidatorValidate card numbers with the Luhn check and detect the card brand.CSP Header GeneratorBuild, validate and analyse Content-Security-Policy headers.CSR DecoderDecode a CSR and verify its signature before sending it to a CA.Hash GeneratorMD5 and SHA hashes of text or files, side by side.HMAC GeneratorKeyed HMAC signatures with SHA-1, SHA-256, SHA-384 or SHA-512.Htpasswd GeneratorMake .htpasswd entries for password-protecting a site with basic auth.JWT EncoderBuild, sign and verify JWTs with HMAC, RSA or ECDSA keys.Key Pair GeneratorGenerate RSA, ECDSA or Ed25519 key pairs as PEM and OpenSSH keys.Passphrase GeneratorCreate strong, memorable passphrases from the EFF diceware word list.Password GeneratorCreate strong random passwords with a secure random generator.Password Strength CheckerEstimate password strength and crack time, privately.PEM to DER ConverterConvert PEM, DER and Base64, split bundles and view the ASN.1 tree.Random Token GeneratorCreate random API keys, secrets and tokens in hex, Base64 or Base62.Secret ScannerFind API keys, tokens and passwords in text and mask them before sharing.Security Headers CheckerGrade pasted response headers and get a recommended security header block.Security.txt CheckerFind and validate a site's security.txt file.SSL Certificate DecoderDecode PEM or DER certificates and check expiry, SANs and chain order.Suspicious Link CheckerCheck links for phishing red flags without opening them.Text Encrypt and DecryptPassword-protect text with AES-256-GCM, and decrypt it again.TOTP Code GeneratorLive 2FA authenticator codes from a TOTP secret.
Design & Colour
Accessible Palette CheckerWCAG contrast grid for a whole palette, with a minimal-change lightness fixer.Aspect Ratio CalculatorSimplify ratios and calculate missing width or height.Border Radius GeneratorRound corners, pills, circles and blob shapes with a live preview.Box Shadow GeneratorBuild layered and inset CSS box shadows with a live preview.Clip Path GeneratorPolygon, circle, ellipse and inset clip-paths with draggable points.Color Blindness SimulatorSimulate colour vision deficiencies on a palette, with clash warnings.Color Palette GeneratorColour harmonies and a Tailwind-style 50–950 scale from one base colour.Colour ConverterConvert between HEX, RGB, HSL and HSV with a live preview.Colour MixerBlend two colours in three colour spaces and build a stepped scale between them.Contrast CheckerWCAG contrast ratio with AA and AAA pass or fail.CSS Gradient GeneratorDesign linear, radial and conic gradients and copy the CSS.CSS Grid GeneratorDrag out named grid areas and copy grid-template-areas CSS with matching HTML.CSS Triangle GeneratorPure CSS triangles and tooltip arrows using borders or clip-path.Flexbox PlaygroundTry every flexbox property on live boxes and copy the resulting CSS.Glassmorphism GeneratorFrosted glass cards with backdrop-filter, previewed live.PX to REM ConverterPixels to rem and back, with any root font size.Text Shadow GeneratorLayered CSS text shadows with neon, 3D, outline and long shadow presets.
Data & Conversion
.env to JSON ConverterConvert dotenv files to JSON, YAML, docker flags or Kubernetes env, and back.CSV CleanerTrim, dedupe and tidy CSV files, with a report of every change.CSV to JSON ConverterTurn CSV or TSV into a JSON array of objects.CSV to SQL ConverterGenerate CREATE TABLE and INSERT statements from CSV data.CSV ViewerOpen CSV data as a sortable, filterable table.HTML Table to CSVExtract tables from HTML into CSV, TSV or JSON.JSON DiffStructural JSON comparison with paths, a side-by-side view and JSON Patch output.JSON to CSV ConverterTurn a JSON array into a spreadsheet-ready CSV file.JSON to XMLTurn JSON objects into indented, valid XML.JSON to YAML ConverterConvert between JSON and YAML in either direction.Markdown Table GeneratorMake and tidy Markdown tables from a grid, CSV or an existing table.Recipe BuilderChain decoders, formatters and converters into one reusable recipe.TOML to JSON ConverterConvert between TOML and JSON, with clear errors and date handling.XML FormatterBeautify, validate and minify XML documents.XML to JSONTurn XML documents into JSON objects, attributes included.
Time & Date
Age CalculatorExact age, total days lived and the next birthday.Business Days CalculatorWorking days between dates or from a date, minus weekends and holidays.Countdown TimerA countdown timer with presets, an alarm and a big display.Cron Expression ParserTurn a crontab schedule into plain English and see its next runs.Date CalculatorAdd or subtract days, weeks, months or business days from a date.Date Difference CalculatorDays, weeks, months and business days between two dates.Days Until CountdownA live, shareable countdown to any date and time.Due Date CalculatorEstimated due date, weeks pregnant, trimester and milestone dates.Julian Date ConverterDates to and from Julian Date, MJD and YYDDD ordinal dates.Leap Year CheckerIs it a leap year? With the rule, next and previous leap years.Meeting PlannerFind the overlapping working hours across time zones.Pomodoro TimerFocus sessions and breaks on the Pomodoro cycle.Sleep CalculatorBedtimes and wake-up times that line up with 90-minute sleep cycles.StopwatchTime anything to the hundredth, with laps and splits.Time Duration CalculatorHours between times, timesheet totals and decimal hours.Time Zone ConverterConvert a time between time zones, daylight saving included.Unix Timestamp ConverterEpoch seconds or milliseconds to readable dates, and back.Week Number CalculatorISO week number of a date, and the dates in any week.World ClockLive local times for your chosen cities around the world.
Network Tools
CIDR to IP Range ConverterConvert between CIDR blocks and IP ranges, merge CIDRs and expand ranges.DNS LookupSee every DNS record for a domain, with TTLs.Domain WHOIS LookupRegistrar, dates, status and nameservers for a domain or IP.Email Authentication CheckerCheck SPF, DKIM, DMARC, MTA-STS and BIMI for a domain.HTTP Header CheckerFetch a URL and see its status code and response headers.IP Address ConverterConvert IP addresses between dotted, integer, hex, binary and octal.IPv6 Expand and CompressExpand, compress and validate IPv6 addresses and prefixes.MAC Address GeneratorGenerate random MAC addresses or reformat and inspect existing ones.Port Number LookupFind the service behind a TCP or UDP port, with security notes.Redirect CheckerFollow a URL's redirects and unshorten short links.Reverse DNS LookupFind the PTR host name for an IP and check it points back.SSL Certificate CheckerCheck a site's certificate expiry, chain and trust.Subnet CalculatorWork out network, broadcast and host range for any IPv4 CIDR block.What Is My IP?Your public IP address, as websites see it.
Generators
Barcode GeneratorMake EAN, UPC, Code 128 and Code 39 barcodes with check digits.Coin FlipFlip one coin or thousands, with counts, percentages and streaks.Dice RollerRoll any dice using notation like 2d6+3 or 4d6kh3, with history and stats.Fake Data GeneratorMake realistic fake rows for testing and export them as JSON, CSV, SQL or NDJSON.Lorem Ipsum GeneratorPlaceholder text by paragraph, sentence or word count.QR Code GeneratorCreate static QR codes for URLs, contacts, email, SMS and more.Random Name PickerDraw random winners from a list or split names into balanced teams.Random Number GeneratorPick random whole or decimal numbers in any range, with no duplicates if you like.Random String GeneratorSecure random strings from any character set.Spin the WheelSpin a wheel of names, choices or prizes to pick one at random.UUID GeneratorGenerate random v4 UUIDs/GUIDs in bulk.Wi-Fi QR Code GeneratorTurn your Wi-Fi name and password into a scan-to-join QR code.
PDF and image tools
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