Free 54 tools · no sign-up · nothing uploaded

The developer toolbox that runs in your browser

Format and validate JSON, tidy SQL, decode Base64 and JWTs, generate UUIDs and convert units: fast, focused tools that work on your data without ever sending it to a server.

54 Tools ready to use

7 Categories covered

100% Client-side processing

Free Cost, forever

Most used

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JSON Formatter Pretty-print JSON with your choice of indentation and optional key sorting. JSON Tools JSON Validator Check JSON syntax and pinpoint errors by line and column. JSON Tools JSON to C# Class Generate C# model classes with inferred types from sample JSON. JSON Tools SQL Formatter Beautify SQL with consistent indentation and keyword case. SQL Tools Base64 Decoder Decode Base64 back to text or a downloadable file. Encoding Tools JWT Decoder Read JWT header and claims. Decoding does not verify the signature. Encoding Tools UUID Generator Generate random v4 or time-ordered v7 UUIDs in bulk. Generators Password Generator Create strong random passwords and passphrases. Generators

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Everything, by category

JSON Tools Format, validate, minify and convert JSON to CSV, XML, C# and TypeScript. 8 tools SQL Tools Format queries and generate CREATE, INSERT and UPDATE statements for SQL Server, PostgreSQL and MySQL. 8 tools Encoding Tools Encode and decode Base64, URLs and HTML entities, and inspect JWT tokens. 7 tools Web Tools Format HTML, CSS and JavaScript, generate meta tags, robots.txt and sitemaps, and convert colors. 8 tools Generators Generate UUIDs, GUIDs, passwords, placeholder text, random numbers and mock data. 7 tools Converters Convert Unix timestamps, dates, data sizes, temperature, length, weight and speed. 8 tools Text Tools Count words, change case, clean up and sort lines, and compare two texts. 8 tools

Hand-picked

Featured tools

JSON to C# Class Generate C# model classes with inferred types from sample JSON. JSON Tools SQL Formatter Beautify SQL with consistent indentation and keyword case. SQL Tools Open Graph Meta Generator Create Open Graph and Twitter Card tags for link previews. Web Tools Color Converter Convert colors between HEX, RGB, HSL, HSV and CMYK. Web Tools Fake JSON Data Generator Create realistic mock JSON records for testing. Generators Text Diff Highlight the differences between two texts. Text Tools

New

Recently added

Line Break Formatter Join, wrap or convert line breaks and line endings. Text Tools Text Diff Highlight the differences between two texts. Text Tools Text Sorter Sort lines alphabetically, numerically or by length. Text Tools Remove Extra Spaces Collapse repeated spaces, trim lines and remove blank lines. Text Tools Remove Duplicate Lines Delete repeated lines while keeping the original order. Text Tools Case Converter Switch text between upper, lower, title, camel and snake case. Text Tools

Why teams use it

Built for everyday development work

Processed in your browser

Tools work on your input with JavaScript on your own device. The JSON, SQL or text you paste is not uploaded to our server.

Fast and focused

Each tool has its own lightweight page that loads only the code it needs, so results appear instantly, even on a phone.

Clear error messages

When input is invalid, tools explain what is wrong and where, such as the exact line and column of a JSON syntax error.

Free, no account

Open a page and start working. There is nothing to install and no sign-up, on desktop, tablet or mobile.

Bookmark SADevToolBox and stop reinstalling utilities

One tab for formatting, encoding, generating and converting. Nothing to install, nothing to sign up for, and your data never leaves the browser.

Browse all tools How it works

Questions

Frequently asked questions

Are the tools really free?

Yes. Every tool on the site is free to use and none of them require an account.

Is my data uploaded when I use a tool?

The tools process your input with JavaScript in your browser, so the text or files you enter are not sent to our server. Our web server does receive the normal request information any website receives, such as the page address and your IP address. Each tool page states how it handles your data.

Do I need to install anything?

No. The tools run in any modern browser on Windows, macOS, Linux, Android and iOS.

Do the SQL tools connect to my database?

No. The SQL tools only format and generate SQL text. They never connect to a database or execute queries.

Can I use the tools offline?

Once a tool page has loaded, the processing itself does not need a network connection. You need to be online to load a page the first time.