Chrome Extension · MV3 · v1.0

A developer toolbox,
in your side panel.

35 tools — JSON, JWT, Base64, regex, UUID, QR, an encrypted vault and more — that follow you to every tab. Press ⌘ Shift D and they're there. No popups, no new windows, no context switch.

Tools
35
Cloud calls
0
Min size
2 MB
Permissions
2
PANEL · 380 × 800 MV3 CHROME 116+ 100% LOCAL DevUtils Sidebar — tool browser in Chrome's side panel
Tool Catalog

35 tools. One ⌘K away.

Every common dev chore — format, encode, decode, parse, hash, generate, compare — under one roof. Open the panel and start typing.

Formatters7
  • JSON · pretty / minify / validate
  • SQL · YAML · XML
  • HTML · CSS · JavaScript
  • Mock data generator
Encoders6
  • Base64 (URL-safe option)
  • URL encode / decode
  • HTML entity
  • Hash · MD5 / SHA-1 / SHA-256 / SHA-512
  • HMAC · SHA-256 / SHA-512
JWT & Auth2
  • JWT decoder · header / payload / expiry
  • JWT generator · HS256 / HS384 / HS512
Generators4
  • UUID v4 · batch
  • Password · crypto-safe with entropy
  • QR codes · 16 designer styles
  • Image converter
Time3
  • Timestamp converter
  • Timezone converter
  • Date diff
Inspectors5
  • Regex tester with all flags
  • URL parser · query string
  • Cron parser · in plain English
  • Diff checker · line / word / char
  • Headers inspector
Text3
  • Counter · chars / words / bytes
  • Case converter · camel / snake / kebab
  • Sorter · dedupe / natural ordering
Workspace · NEW2
  • Notes · markdown scratchpad
  • Vault · encrypted local store
VAULT · UNLOCKED
Production DBLOGIN
Bastion SSH keySSH
.env · stagingENV
OpenAI keySECRET
ON-DISK FORMAT
{ kdf: PBKDF2-SHA-256,
  iterations: 600 000,
  cipher: AES-GCM-256,
  ciphertext: … (opaque) … }
New in v1.0 · Vault

An encrypted vault for the secrets you'd normally paste into Notes.

Env files, SSH keys, API tokens, server logins — kept on this device, encrypted with a key derived from a passphrase you alone know. We never see it. There's no recovery.

  • AES-GCM-256 with a key derived from your passphrase via PBKDF2-SHA-256, 600 000 iterations.
  • Auto-lock after 15 min idle. Derived key wiped from memory on lock, on panel close, on browser quit.
  • Clipboard auto-clears ~30 s after every secret you copy.
  • One-click encrypted backup you can save anywhere on your machine.
Privacy by design

Your data never leaves your device.

We measured this. The extension has zero host_permissions and makes zero outbound network requests at any time.

No accounts

You don't sign up, sign in, or hand us an email. There is no us-side account. There is no us.

No telemetry

No analytics scripts, no error reporters, no pings. The extension is bundled at build time — there's no remote code.

No cloud

Preferences live in chrome.storage.local. The Vault is encrypted at rest — even we couldn't read it.

Read the full privacy policy

Try every tool right now,
in this browser.

The same React app, bundled as a website. No install, no sign-up. Anything you do — values you enter, secrets you store — stays in localStorage on this device.

The live demo runs the exact same code as the extension. Bookmarkable as a standalone PWA.