About these developer tools
Developers keep a short list of small utilities close at hand: a JSON formatter, an encoder, a hash tool and a regex tester. Having them in one place with no ads before the tool and no sign up saves a lot of clicks.
Because everything runs client side, you can paste tokens, payloads and logs without sending them to a third party server. Still, avoid pasting live secrets into any website out of habit.
What each tool does
- JSON Formatter and Validator: Paste your JSON and the tool checks that it is valid, then formats it with indentation or compresses it into one line. Errors are explained in plain words.
- Base64 Encoder and Decoder: Base64 turns text or bytes into a safe string of letters and numbers. Choose encode or decode, paste your input and copy the result.
- URL Encoder and Decoder: URL encoding replaces unsafe characters with a percent sign and two hex digits so a link works everywhere. Paste text to encode or decode it.
- Hash Generator: A hash is a fixed length fingerprint of your text. Enter text to get its SHA 1, SHA 256, SHA 384 and SHA 512 hashes, calculated locally in your browser.
- Regex Tester: Enter a pattern, flags and test text. The tester lists every match with its position and capture groups so you can debug a regular expression quickly.
- CSS Minifier: Paste your CSS and the minifier removes comments and extra whitespace to make the file smaller, with the size saved shown.
- HTML Minifier: Paste your HTML and the minifier removes comments and extra whitespace between tags to reduce file size without changing how the page looks.
- SVG Optimizer: Paste your SVG code and the optimizer strips comments, metadata and editor leftovers and rounds long decimals, then shows a preview and the size saved.
- Unix Timestamp Converter: A Unix timestamp counts the seconds since 1 January 1970 UTC. Paste a timestamp to see the date, or choose a date to get the timestamp.
- JSON to CSV Converter: Paste a JSON array of objects to get CSV rows with a header, or paste CSV to get JSON. Quotes and commas inside values are handled correctly.
- JWT Decoder: Paste a JWT to see its header, payload, algorithm and expiry time. The tool decodes only and does not verify the signature, and nothing is sent anywhere.
- JSON Minifier: Paste JSON to remove all extra spaces and line breaks. The tool validates the data first and shows how many characters you saved.
- JavaScript Minifier: Paste JavaScript to strip comments and extra whitespace. It is a safe minifier that does not rename variables, and it shows how much size you saved.
- CSS Gradient Generator: Choose two colors, a gradient type and an angle. The tool shows a live preview and gives you the CSS background code to paste into your stylesheet.
- CSS Box Shadow Generator: Set the offsets, blur, spread, color and opacity to see the shadow on a preview card, then copy the box shadow CSS line for your project.
- Subnet Calculator: Enter an IPv4 address and a prefix length such as 24. The calculator returns the network, subnet mask, broadcast address and the range of usable hosts.
How to choose the right tool
Use the JSON formatter when an API response is hard to read. Use Base64 and URL tools when debugging requests. Use the hash tool for checksums and the regex tester to refine patterns before you commit them.
These tools help with everyday debugging. They do not replace unit tests, code review or security audits.
Frequently asked questions
Is my data uploaded?
No. Processing happens in your browser.
Which regex flavor does the tester use?
JavaScript.
Why no MD5 in the hash tool?
Browsers do not provide MD5 and it is not safe for security use.
Can I use these offline?
After the page loads, yes.
Need something we do not offer, such as page speed tests or keyword volume? See our directory of trusted free tools.