How to Decode Base64 Online for Free — Browser-Based Tool
Decode Base64-encoded strings back to plain text or binary data in your browser. No data sent to any server.
Decode Base64 Online — Free & Private
Decode Base64-encoded strings back to plain text or binary data entirely in-browser — ideal for inspecting JWT payloads, email attachments, API responses, and encoded credentials without sending sensitive data to any server.
Base64 encoding is used throughout web development for JWTs, email MIME parts, and API authentication headers. This decoder converts Base64 back to readable text locally in your browser.
How to Decode Base64 Online
Step 1: Paste Your Base64 String
Paste the Base64-encoded string into the input field. The tool accepts standard and URL-safe Base64 variants.
Step 2: Click Decode
Press the Decode button. The browser decodes the string locally using the built-in atob() function.
Step 3: View the Decoded Output
The plain text or binary output appears instantly in the output panel, with character encoding information shown.
Step 4: Copy the Result
Click Copy to clipboard to use the decoded text in your application or debugging workflow.
Why Use This Decoder?
Completely Private
Your encoded data and decoded secrets never leave your browser — critical for credentials and tokens.
Instant Decoding
Uses the browser's native atob() function for immediate, zero-latency decoding.
Both Variants Supported
Accepts standard Base64 and URL-safe Base64 (used in JWTs and OAuth tokens).
Decode Base64 Now — No Upload Required
Runs entirely in your browser — no upload, no account, no waiting.
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