29 tools

Development tools

The small detours of a working day: pretty-printing a JSON payload, decoding a JWT to see why it expired, generating a UUID, checking what a DNS record actually resolves to. Pasting any of that into a random website means handing over data you often should not: tokens, customer exports, internal hostnames. Everything here runs locally in your browser instead, which is the whole point.

Base64 Encoder / DecoderEncode and decode Base64 strings with UTF-8 support

Cron Expression BuilderOnline cron editor: build, parse and preview the next run times

CSS Layout PlaygroundVisual playground for CSS Flexbox and Grid with live preview and code output

CSV ⇄ JSON ConverterConvert CSV to JSON and back: auto-detects delimiter, handles quotes, types numbers

CSV EditorOpen, edit and save CSV files in a spreadsheet grid, with live two-way file sync

NewcURL ConverterConvert cURL to fetch, axios, Python or HTTPie, build HTTP requests and send them from the browser

Diagram Editordrawio-compatible diagram editor: open, edit and create .drawio files with multi-page, Mermaid import, auto-layout, share-by-link, version diff and PNG/SVG export with embedded XML

Diff CheckerCompare two texts line by line with additions, deletions and unchanged lines highlighted

DNS LookupCompare A, MX, TXT, CNAME records on Google and Cloudflare, spot propagation, export a BIND zone

Duration ConverterConvert minutes to hours, days, seconds and back in one step

Favicon GeneratorGenerate all favicon sizes and formats from a single image

Hash GeneratorGenerate MD5, SHA-1, SHA-2, SHA-3 and BLAKE2b hashes from text or files