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astound.tools / jwt-debugger
client-side
Astound DevTools — JWT Debugger tool showing an encoded JWT token being decoded into its header and payload sections, with signature verification, all running client-side in the browser
28 tools · 8 categories · one keystroke away

Every tool you reach for, all in one place.

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SEC

Security & Auth

05 tools

JWT · certs · hashing · package audit

Decode and verify tokens, inspect TLS certificates, hash and audit dependencies — every check runs on your machine, nothing reaches a server.

JWT decode & verifySSL/TLS inspectionMD5 → SHA-512Package audit
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LLM

AI & LLM Tooling

04 tools

tokens · cost · prompt diff

Count tokens and cost across GPT-4, Claude, and Gemini. Validate MCP schemas.

Token counterMCP validator
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ENC

Encoding & Data

08 tools

JSON · Base64 · UUID · diffs

Format, validate, and transform any structure — JSON, Base64, UUID, and diffs.

JSON formatterBase64 anything
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NET

Web & Network

04 tools

WHOIS · DNS · SSL · OG · cron

Domain health end-to-end: WHOIS, DNS, SSL, IP geo, OG previews, and cron.

WHOIS + DNSCron builder
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DOC

Media & Docs

03 tools

image · EXIF · PDF · MDX

Compress and convert images, strip EXIF, export PDF, preview MDX — all local.

Image compressionEXIF remover
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PRIV · ALL CHANNELS

Safe to use with real data.

SELF-HOST

Paste production tokens, API secrets, private certificates, or sensitive JSON with confidence. Every tool runs entirely in your browser tab — and with the self-hosted deployment, it never leaves your own network.

No server, no logsWorks fully offlineNo sign-upNo fingerprinting
NETWORK · egress
fetch()blocked
XHRblocked
analyticsdisabled

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Free forever · Open source · MIT licensed