Essential developer utilities — encode, hash, test, generate. All tools are 100% free, require no sign-up, and every one runs entirely in your browser — nothing is ever uploaded.
Your AI pair programmer — explain, debug, convert, generate
8 AI-powered coding actions in one studio. Explain any code in plain English, debug and fix errors, convert between languages, refactor messy code, generate from description, add documentation, write unit tests, and build regex patterns.
def fibonacci(n):
if n <= 1: return n
return fib(n-1) + fib(n-2)
# NameError: fib is not defined
Bug: rename fib → fibonacci
Prettify, minify, and validate JSON. Syntax highlighting with error detection.
Generate QR codes from URLs or text. Custom colors and logo. Download PNG/SVG.
Generate strong random passwords. Custom rules, strength meter, batch mode.
Encode and decode text or files to Base64. Fast, free, in-browser.
Encode and decode URL components. Handle special characters for query strings.
Decode JWTs, run health checks, and verify HS256/384/512 signatures locally.
Prettify, minify, and validate JSON. Syntax highlighting with error detection.
Validate and pretty-print YAML — with error line numbers and key sorting.
Beautify minified JavaScript, CSS, HTML, and JSON with a live preview.
Format and beautify SQL for PostgreSQL, MySQL, T-SQL, and 7 more dialects.
Minify JavaScript, CSS, HTML, and JSON — with live byte savings.
Encode and decode text or files to Base64. Fast, free, in-browser.
Encode and decode URL components. Handle special characters for query strings.
Encode special HTML characters to entities and decode entities back to HTML.
Convert Unix timestamps to human-readable dates and back. Multi-timezone.
Convert numbers between binary, octal, decimal, hex, and any base 2–36.
Convert JSON to CSV and CSV back to JSON — with proper quoting and type coercion.
Generate TypeScript interfaces from a JSON sample — nested types included.
Convert JSON to YAML and YAML back to JSON — losslessly, both directions.
Convert JSON to XML and XML back to JSON — attributes preserved, both directions.
Generate strong random passwords. Custom rules, strength meter, batch mode.
Decode JWTs, run health checks, and verify HS256/384/512 signatures locally.
Generate MD5, SHA-1/256/512 & SHA-3 hashes — or keyed HMACs — from text or files.
Generate and verify bcrypt password hashes with an adjustable cost factor.
Build linear and radial CSS gradients visually. Copy CSS code with one click.
Pick any color and convert between HEX, RGB, HSL, and CMYK formats instantly.
Check colour contrast against WCAG AA/AAA, with a live text preview.
Design CSS box-shadows visually with a live preview and copy-paste output.
Round corners visually — link or independently — with live preview and CSS.
Design CSS easing curves with draggable handles and a live animation preview.
Test regular expressions live. See all matches highlighted in real time.
Explain a cron expression in plain English and preview its next run times.
Searchable reference of HTTP status codes with plain-English meanings.
Calculate Unix file permissions — octal, symbolic, and the chmod command.
Build a .gitignore from language, tool, and OS templates — combine any stacks.
Look up MIME types by file extension — or extensions by MIME type.
Built for speed, privacy, and quality — no bloated apps or subscriptions needed.
Generate QR codes with custom colors, sizes, and error correction.
Decode and inspect JWT tokens — header, payload, and signature.
Live regex matching with flags, match groups, and replace preview.
MD5, SHA-1, SHA-256, SHA-512 hashing. Compare and verify instantly.
Encode/decode Base64 strings and files. Supports binary data.
Visual gradient builder with live preview and copy-ready CSS output.
Popular use cases
Everything you need to know about our developer tools.
Yes — all developer tools run entirely in your browser. Hashing, encoding, decoding, regex testing, JWT decoding, and QR code generation are all client-side operations. Nothing is sent to a server.
Yes — QR codes you generate are yours to use for any purpose including commercial use. There are no watermarks. Download as a high-resolution PNG.
Yes. JWT decoding is done entirely in your browser using JavaScript. Your tokens are never sent to any server. Note: the decoder shows token contents but does not validate signatures — use your backend for signature verification.
No. Generated passwords exist only in your browser's memory and are never transmitted anywhere. Close the tab and they're gone. For best security, copy the password immediately and store it in your password manager.
33 tools, completely free, no account needed. Start with our most popular tool.