100 tools · 100% in-browser · no data sent
Your everyday technical toolbox,
and your data stays with you.
100 free tools for coding and running your business, from JSON formatting to VAT calculation, all running entirely in your browser. Pin your favorites to your startpage to find them there every morning.
- Free, no account
- Client-side encryption
- Hosted in France
- GDPR-ready
Every tool below runs entirely in your browser — your data never leaves your device, so you can verify it in DevTools. No sign-up, no upload, no tracking. Format JSON, test regular expressions, decode JWTs, generate hashes, convert data and dozens more, all free.
Caesar shift, ROT13, ROT47 and automatic brute-force.
Generate random names for projects, teams or usernames.
Generate strong, random passwords.
Count words, characters, sentences and reading time.
Track your hours: multiple segments per day, auto totals, export and print.
Encrypt and decrypt with Vigenère, Beaufort and autokey.
Find your IP address and its information.
Write Markdown and preview the rendered output in real time.
Compute MD5, SHA-1, SHA-256 and SHA-512 hashes of text.
Generate random UUID v4 identifiers.
Generate a QR code from text or a URL.
Calculate mean, median, mode, standard deviation and more.
Test regular expressions with highlighted match visualization.
Compress your JSON by removing unnecessary whitespace.
Convert text case: UPPER, lower, Title, camelCase, snake_case.
Spin the wheel for a random choice among your options.
2×2 matrix cipher modulo 26.
Calculate cross multiplication instantly.
Pomodoro timer: 25 minutes of focus, 5 minutes of break.
Convert your images between PNG, JPG and WebP.
Search and copy emojis in one click.
Convert TOML to JSON and back.
Generate Lorem Ipsum placeholder text for your mockups.
Convert colors between HEX, RGB and HSL formats.
Stopwatch and countdown timer with sound alert.
Compress your PNG, JPG and WebP images directly in the browser.
Generate a multi-size favicon from an image.
Fix broken JSON and reformat it.
Hex, binary, int64, float and ASCII with endianness.
Add a text, IP or logo watermark to your images.
The Atbash cipher: A↔Z, B↔Y… alphabet reversal.
Translate text ↔ morse, with sound playback.
Bacon's biliteral cipher (5-symbol a/b codes).
Zigzag transposition cipher.
Digraph cipher with a 5×5 key square.
Letter, bigram and trigram frequency.
Encode each letter as coordinates on a 5×5 grid.
Convert letters to their rank (A=1, Z=26).
(a·x+b) mod 26 cipher with modular inverse.
Vigenère variant with a numeric key.
Encode or decode text to/from Base32 (RFC 4648).
Encode or decode with Base58 (Bitcoin alphabet).
Format and indent your JSON instantly.
Check whether your JSON is syntactically valid.
Remove duplicate lines from a list.
Generate URL-friendly slugs from any text.
Compare two texts and visualize the differences.
Convert JSON to CSV.
Convert JSON to XML.
Convert JSON to YAML.
Convert YAML to JSON.
Convert JSON to TOML.
Convert TOML to JSON.
Convert a CSV file to JSON instantly.
Convert XML to structured JSON.
Encode or decode text to/from Base64.
Encode or decode strings for use in URLs.
Encode or decode HTML entities.
Convert Unix timestamps to readable dates and back.
Parse a cron expression and preview the next execution times.
Inspect the HTTP response headers of any public URL.
Convert JSON to YAML and back.
Sort, clean and reorganize your text.
Decode and verify JWT signatures directly in your browser.
Convert numbers between binary, octal, decimal and hexadecimal.
Calculate percentages: X% of Y, proportion, variation.
Convert between units of length, weight, temperature, volume and area.
Calculate the number of days between two dates or until a date.
Simple task list with local and online saving.
Simple notepad with local and online saving.
Personal calendar with events. Login required.
Randomly draw one or more items from a list.
Generate TypeScript interfaces from JSON.
Generate Go structs from JSON.
Generate HTML meta tags for SEO and social networks.
Scientific calculator with advanced functions.
Convert between JSON, YAML, TOML, CSV and XML.
Share an encrypted message: expiry, self-destruct and optional password.
Upload a file and get an anonymous download link.
Estimate the number of LLM tokens in a prompt (GPT, Claude).
Convert an image to a Base64 data URI (CSS, img tag).
Check an IBAN, a French SIRET/SIREN or VAT number.
Build multi-color CSS gradients (linear, radial, conic).
Clean up and shrink an SVG file.
Create a 1200×630 social share image as PNG.
Upscale or downscale an image (px or %).
Edit a folder from your PC in the browser — local and private.
Generate a paper card/matrix to note your passwords safely.
Encrypt or crack a substitution cryptogram.
Build multi-layer CSS shadows with a live preview.
A complete developer toolbox that runs in your browser
Toolab brings together 100 free tools for developers and technical users: JSON formatting and validation, regular-expression testing, hash and password generation, JWT decoding, conversion between formats (CSV, XML, YAML), Base64, Base32 and Base58 encoding, and a full collection of classical ciphers. No account is required and there is nothing to install.
Every tool runs locally in your tab — your files, text and keys are never sent to a server, which you can confirm yourself in your browser's network tab. For developers who would rather not paste a production token into jwt.io or secrets into a random website, that verifiable privacy is the whole point.
Beyond formatting and converting, Toolab includes encrypted secret notes and file drops that self-destruct, image compression and resizing, a local-first code editor, and dozens of generators and converters. Pin your favourites to your start page to keep them one click away every morning.