Base64, JWT & URL Decoder
Encode and decode Base64, inspect JWT tokens, and URL-encode strings — all in your browser. Tokens and secrets never leave your device, which is exactly how it should be.
Your file never leaves your device — there's no upload step at all. You can verify it: open your browser's DevTools → Network tab and watch as you use the tool. Zero file uploads.· Updated July 2026.
Vira's brief
Use the tool locally, download the result, and contact VNG only when this needs to become a repeatable workflow.
// output appears here
How it works
- 1
Pick a tab
Base64, JWT, or URL — each works on the text you paste.
- 2
Paste and decode
JWTs are split into pretty-printed header and payload; Base64 and URL work both directions.
- 3
Copy the result
One click copies the decoded output.
Frequently asked questions
Is it safe to paste a JWT here?
Safer than anywhere else: decoding happens in your browser with JavaScript — the token is never transmitted. Never paste production tokens into tools that send them to a server.
Does the JWT tab verify the signature?
No — it decodes the header and payload for inspection only. Signature verification requires the signing key and should happen in your backend.
Why does my Base64 fail to decode?
Usually whitespace/newlines inside the string or a URL-safe variant. This tool handles standard Base64; the JWT tab handles the URL-safe variant automatically.
Does it handle Unicode?
Yes — encoding and decoding are UTF-8 aware, so emoji and non-Latin scripts round-trip correctly.
Need this at scale — or something custom?
This tool runs entirely in your browser — that's the same privacy-first engineering we build for companies: dashboards, AI automation, data pipelines, and client platforms. One person, senior work, fast turnaround.
— Amit, VritantaNextGen · replies within 24 hours