$ cat about.txt

404.bd is a free collection of developer tools in a terminal-style interface — JSON formatter, JWT decoder, regex tester, cron builder, hash generator, and more, all in one place.

Every tool here runs entirely in your browser. Nothing you paste into a formatter, decoder, or tester is ever uploaded anywhere — which makes these tools safe for working with tokens, credentials, and code you'd rather not send to a random server. They're fast, they work offline once loaded, and they require no sign-up.

The site is built and maintained by Hossain Sajjad, a developer from Dhaka, Bangladesh. It's kept free by unobtrusive ads on tool pages.

Found a bug, want a new tool added, or just want to say the terminal theme is cool? Reach out: from.hossainsajjad@gmail.com

$ exit