Developer tools
Format, convert, encode, test and generate, all in your browser. Paste code or data without it ever being uploaded.
The tools
See every ZapKit toolJSON & data
4 toolsFormat and validate JSON, and convert it to CSV, YAML or TypeScript types.
- JSON formatter & validatorPretty-print, minify, sort and validate JSON with line-numbered errors.
- JSON ↔ CSV converterConvert JSON arrays to CSV and CSV back to JSON.
- JSON to TypeScriptGenerate TypeScript interfaces or types from a JSON sample.
- JSON ↔ YAML converterConvert JSON to YAML and YAML to JSON.
Encoding & security
4 toolsBase64, URL encoding, JWT decoding and MD5, SHA-1 and SHA-256 hashes.
- Base64 encode & decodeBase64 and Base64url for text (UTF-8) and files.
- URL encode & decodePercent-encode or decode URLs and query values, and see a URL's parts.
- JWT decoderDecode a JSON Web Token's header and payload and check its expiry.
- Hash generatorMD5, SHA-1 and SHA-256 hashes of text or files, with checksum compare.
Text & code
5 toolsRegex tester, text diff, cron explainer, lorem ipsum and Markdown preview.
- Regex testerTest JavaScript regular expressions with live highlighting, groups and replace.
- Text diff checkerCompare two texts by line, word or character and see what changed.
- Cron expression explainerTranslate a cron schedule into plain English and see its next run times.
- Lorem ipsum generatorPlaceholder text by paragraph, sentence or word, plain or in <p> tags.
- Markdown previewerLive Markdown preview with GitHub tables and code blocks, and HTML output.
Colours
3 toolsColour picker, HEX/RGB/HSL conversion and WCAG contrast checks.
CSS generators
4 toolsGradients, box shadows, border radius and fluid clamp() sizes.
- CSS gradient generatorLinear, radial and conic gradients with up to six stops.
- CSS box-shadow generatorLayered, inset and soft shadows with a live preview.
- CSS border-radius generatorRounded corners, linked or per-corner, in px or %.
- CSS clamp() generatorFluid font sizes and spacing that scale between two viewport widths.
Formatters
3 toolsBeautify or minify HTML, CSS and JavaScript.
Frequently asked questions
Is it safe to paste code or data here?
The tools run entirely in your browser and don't send what you paste anywhere. Still, treat production secrets, tokens and private keys with care and don't paste them into any website.
Which libraries do the tools use?
Most are written from scratch. Well-tested libraries handle the hard parts: yaml for YAML, jsdiff for diffs, marked and DOMPurify for Markdown, js-beautify for formatting and Terser for JavaScript minification, each loaded only on the page that needs it.
Do the tools work offline?
Once a tool page has loaded, everything except the first load of the JavaScript minifier works without a connection.
Can I share a setup with a colleague?
Tools with small settings, such as the regex tester, cron explainer and CSS generators, keep them in the link. Pasted data isn't put in links.