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Encode, decode, format, validate, convert and analyze data directly in your browser.

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The 15 most popular tools

The utilities developers, analysts and office users reach for every day.

Base64 Encoder
Convert any text, including emoji and accented characters, into a Base64 string in one click.
Encoding & Decoding
Base64 Decoder
Paste a Base64 string and read the original text instantly, even when the padding is missing.
Encoding & Decoding
JSON Formatter & Beautifier
Turn a minified or messy JSON document into readable, consistently indented text, with a precise error message if the JSON is invalid.
JSON & Data
JSON Validator
Check whether a piece of text is valid JSON and locate the exact character where it goes wrong.
JSON & Data
JSON Repair
Paste almost-JSON from a log, a chat answer or a JavaScript snippet and get valid JSON back, with a clear report of every change.
JSON & Data
JWT Decoder
Paste a JWT to read its header and payload as formatted JSON, with issue, not-before and expiry times translated to real dates. Decoding is not verification.
Developer Tools
UUID Generator
Create one or thousands of universally unique identifiers in any version, formatted exactly the way your code or database expects.
Developer Tools
SHA-256 Hash Generator
Hash any text with SHA-256 and get the 256-bit digest as hex or Base64 in real time.
Hash & Checksum
Unix Timestamp Converter
Paste an epoch value or a date and get every common representation at once: seconds, milliseconds, ISO 8601, RFC 2822, local time and relative time.
Date & Time
URL Encoder
Make any text safe for a URL: spaces, accents, ampersands and emoji become %XX sequences.
Encoding & Decoding
URL Decoder
Turn %20, %3A and %C3%A9 back into readable text, and find out exactly where a malformed sequence sits.
Encoding & Decoding
Text Diff – Compare Two Texts
Paste an original and a modified text to see exactly what was added and removed, at the level of detail you choose.
Text Tools
CSV to JSON Converter
Turn CSV rows into clean JSON in one step, with typed values, custom delimiters and pretty or minified output.
JSON & Data
JSON to CSV Converter
Paste a JSON array and get a CSV file ready for Excel or Google Sheets, with nested data flattened into columns.
JSON & Data
Regex Tester
Write a pattern, paste some text and see every match highlighted, with its position and capture groups.
Developer Tools

Tool categories

Everything is organized by task so you can find the right tool in seconds.

Developer Tools

38 tools

Encoding & Decoding

26 tools

JSON & Data

39 tools

Hash & Checksum

10 tools

Text Tools

19 tools

Date & Time

10 tools

Network Tools

10 tools

File Tools

9 tools

Markdown & Diagrams

12 tools

Your data stays in your browser

Nearly every tool on this site runs as JavaScript inside your own browser tab. What you paste or drop into a tool is processed on your device and is never sent to our servers.

Local processing
Text, JSON, JWTs, CSV files and archives are processed by your browser, not by a server.
No accounts
There is nothing to sign up for. No login, no profile, no tracking of what you type.
No stored content
Inputs and files are never saved. We only remember tool names you favourite, in your own browser.
Open-source engines
Built on well-known open-source libraries, credited on our open-source page.

Frequently asked questions

Are these tools really free?

Yes. Every tool is free to use with no account, no daily limit and no watermark.

Is my data uploaded anywhere?

No. The tools run in your browser, so pasted text and dropped files stay on your device. You can verify this by using the site with your network disconnected after the page has loaded.

Can I use the tools offline?

Once a tool page has loaded, most tools keep working without a connection because the processing code is already in your browser. A dedicated offline mode is planned.

Which languages are supported?

The site is available in English, French, Spanish and Arabic (with right-to-left layout). Every tool has a localized address.

Are the results safe to rely on?

Tools follow the relevant standards, but you remain responsible for how results are used. For example, decoding a JWT does not verify its signature, and a matching hash does not prove a file is safe.