DevKit Labs

Convert CSV to JSON and back, with quoted fields and custom delimiters — 100% in your browser.

Turn a cURL command into fetch, Axios, Python, Go, PHP or Ruby — 100% in your browser.

Convert HTML to React JSX — class→className, inline styles to objects — 100% in your browser.

Generate types from a JSON sample in TypeScript, Go, Rust, Python, Java, C# or Kotlin — 100% in your browser.

Convert Markdown to HTML and HTML back to Markdown — GitHub-flavored, 100% in your browser.

Convert numbers between binary, octal, decimal, hexadecimal and any base 2–36 — 100% in your browser.

Convert between Unix timestamps and human-readable dates — with a live epoch clock, 100% in your browser.

Convert TOML to JSON and back — tables, arrays and typed values, 100% in your browser.

Convert XML to JSON and back, with attributes and nested elements — 100% in your browser.

Convert YAML to JSON and back — config-friendly and accurate, 100% in your browser.

Add or remove backslash escaping for strings — newlines, tabs, quotes and Unicode — in your browser.

Encode text to Base64 or decode it back — with URL-safe and file support, 100% in your browser.

Convert text to hexadecimal and hex back to text, UTF-8 aware — 100% in your browser.

Encode text to HTML entities or decode them back — including named and numeric entities, 100% in your browser.

Build and sign a JSON Web Token with HS256 or RS256 — in your browser, no key ever uploaded.

Decode and inspect a JSON Web Token's header, payload and claims — and verify HMAC signatures, 100% in your browser.

Percent-encode or decode URLs and query strings — with a parameter parser, 100% in your browser.

Minify CSS to shrink it or beautify it for readability — string-safe, 100% in your browser.

Beautify messy HTML with clean indentation, or minify it to shrink page weight — in your browser.

Paste HTML and see it rendered live in a safe sandbox — 100% in your browser.

Beautify JavaScript for readability or minify it with Terser — 100% in your browser.

Format, validate and minify JSON instantly — 100% in your browser.

Test JSONPath expressions against JSON and list every path in a document — 100% in your browser.

Format and beautify SQL queries, or minify them to one line — 100% in your browser.

Optimize and minify SVG files with SVGO — strip metadata, round numbers and shrink file size, in your browser.

Preview SVG markup, see its size, and copy a minified version — safely, 100% in your browser.

Format, validate and minify XML instantly — 100% in your browser.

Evaluate XPath expressions against XML and see the matching nodes — 100% in your browser.

Generate placeholder text — paragraphs, sentences, words or lists, with optional HTML — 100% in your browser.

Generate realistic fake data from a custom schema as JSON, CSV or SQL — 100% in your browser.

Create custom QR codes for URLs, Wi-Fi, contacts and more — download as PNG or SVG, 100% in your browser.

Generate UUIDs, ULIDs and NanoIDs in bulk — cryptographically secure and 100% in your browser.

Convert text between camelCase, snake_case, kebab-case, Title Case and 10 more — instantly and privately.

Test regular expressions with live match highlighting, capture groups and replace — 100% in your browser.

Turn any title into a clean, URL-friendly slug — accents transliterated, 100% in your browser.

Sort lines alphabetically, naturally or by length, and remove duplicates — 100% in your browser.

Inspect a string's length, encoding and every character's code point — 100% in your browser.

Compare two blocks of text and highlight the differences line by line — 100% in your browser.

Count words, characters, sentences and reading time as you type — with keyword density, 100% in your browser.

Hash passwords with bcrypt or Argon2id and verify them against a hash — entirely in your browser.

Decode a PEM certificate to read its subject, issuer, validity, SANs and fingerprints — in your browser.

Generate MD5, SHA-1, SHA-256, SHA-384 and SHA-512 hashes from text or a file — 100% in your browser.

Generate strong, random passwords and passphrases with a live strength meter — 100% in your browser.

Generate a 2048, 3072 or 4096-bit RSA public/private key pair in PEM format — entirely in your browser.

Understand any cron expression in plain English and preview its next run times — 100% in your browser.

Look up and explain a domain's DMARC record — policy, reporting and alignment — on our server.

Look up a domain's DNS records — A, AAAA, MX, TXT, NS, CNAME, SOA and CAA — with TTLs.

Resolve a domain to its IPv4 (A) and IPv6 (AAAA) addresses — resolved on our server.

Open a .har file to see every request, status, size, timing and a waterfall — 100% in your browser.

Search and browse every HTTP status code with plain-English meanings — 100% in your browser.

Measure your real download, upload, ping and jitter against Cloudflare's global network — right in your browser.

Calculate network, broadcast, host range and subnet mask from an IPv4 CIDR — 100% in your browser.

Convert an IPv4 address to its IPv6 forms — mapped, compatible, 6to4 and expanded.

Press any key to see its JavaScript event.key, event.code and keyCode — 100% in your browser.

Find a domain's MX (mail server) records with their priorities — resolved live on our server.

Look up and explain a domain's SPF record — every mechanism and the final policy — on our server.

Break a URL into protocol, host, path, query and fragment — 100% in your browser.

Look up a domain's registrar, creation and expiry dates, name servers and status — via RDAP.

Pick a color and convert between HEX, RGB, HSL, HWB, CMYK, LAB, LCH and OKLCH — 100% in your browser.

Generate complementary, analogous, triadic and monochromatic palettes from a base color — in your browser.

Check text/background contrast against WCAG AA and AAA — with a live preview, in your browser.

Build linear, radial and conic CSS gradients with a live preview — copy the CSS in one click.

Generate lighter tints and darker shades of any color as a swatch strip — copy any hex.

Design layered CSS box-shadows with sliders and a live preview, then copy the code.

Create the frosted-glass (glassmorphism) effect with backdrop-blur and transparency — live preview and copy.

Calculate your exact age in years, months and days — and days to your next birthday.

Count working days between two dates, or add business days to a date — weekends excluded.

Count down to any date and time with a live days-hours-minutes-seconds display.

Find the exact duration between two dates in years, months, days, weeks and hours.

A precise online stopwatch with lap times — 100% in your browser, no install.

Convert a time across cities and time zones at once — DST-aware, 100% in your browser.

See the current time in cities and time zones around the world, updating live.

Test your webcam with a live preview, resolution and FPS — 100% in your browser, nothing uploaded.

Test your microphone with a live level meter, then record a clip and play it back — in your browser.

Turn your webcam into a mirror with zoom, brightness and fullscreen — 100% in your browser.

A clean, auto-saving notepad in your browser — no account, works offline.

Work out percentages, ratios and percentage change instantly — in your browser.

Generate random numbers in any range — unique picks, dice, coins — 100% in your browser.

A full scientific calculator with trig, logs, powers, roots and factorials — in your browser.

Record your screen, a window or a tab — with optional mic — no install, 100% in your browser.

A simple checklist that auto-saves in your browser — no account, works offline.

Test your typing speed and accuracy. Get your words-per-minute (WPM) in 15, 30 or 60 seconds — entirely in your browser.

Convert length, weight, temperature, volume, speed, area, time and data — 100% in your browser.

Record audio from your microphone with a live level meter, then play back and download — in your browser.

Convert an image to a Base64 data URI, or decode Base64 back to a downloadable image — in your browser.

Turn one image into a full favicon pack — .ico, PNGs, apple-touch and PWA icons — zipped, in your browser.