Unix Timestamp Converter
Convert epoch seconds/milliseconds to human time and back—with UTC and local views.
Privacy-first · runs in your browser
Small tools. Clear explanations. No account required.
PlainDev Tools is a focused toolkit for everyday backend and API work: timestamps, cron schedules, JWTs, UUIDs, and Base64—paired with guides you can actually finish.
Tools
Each tool page includes a working utility plus enough context to use it safely. Inputs stay on your device.
Cron Expression Explainer
Paste a five-field cron string and read a plain-English schedule summary.
JWT Decoder
Decode header and payload locally. Nothing is sent to a server.
UUID Generator
Generate UUID v4 values in bulk for fixtures, tests, and migrations.
Base64 Encode / Decode
Encode or decode text safely in the browser. Includes a reminder that Base64 is not encryption.
From the blog
Practical write-ups that match the tools—not keyword stuffing.
Why this site exists
Search results for common developer utilities are often slow, ad-heavy, or unclear about whether your data leaves the browser. We keep the utilities tiny, document the edge cases, and publish a privacy policy and terms from day one—because that is what a real site needs before advertising networks will even look at it.
Start with the privacy-first tools guide or theAPI timezone debugging checklist.