$ ls /tools
Developer Tools
A small collection of utilities I reach for daily — built for the terminal-loving developer. Decode JWTs, format JSON, look up HTTP status codes, convert epochs, parse user agents, and more. Everything runs in your browser; no input is ever transmitted.
Tip: on the homepage, hit ⌘K for an interactive terminal that runs every tool in one place.
JWT Decoder
Header, claims, expiry, issuer and security analysis — all in your browser.
open →Base64 Encoder / Decoder
Auto-detects whether to encode or decode. UTF-8 safe.
open →JSON Formatter
Pretty-print, minify, sort keys, diff two documents, and pinpoint parse errors.
open →HTTP Status Code Lookup
70+ codes — IANA standard plus Cloudflare, Nginx, IIS, and AWS ELB extensions.
open →Epoch & Unix Timestamp Converter
Auto-detects seconds, milliseconds, microseconds and nanoseconds.
open →Timezone Converter
35+ aliases including Sweden, Nordics, full Europe, US, India and Asia-Pacific.
open →User-Agent Parser
Browser, engine, OS, device and CPU — your own UA loaded by default.
open →Cron Expression Explainer & Builder
Bidirectional — explain a cron, or describe a schedule and get the cron back.
open →