How do I encode or decode Base64 online?

Paste your text, choose Encode or Decode — the tool auto-detects the input and converts it instantly in your browser.

Base64 is a way to represent binary data as plain ASCII text using 64 characters (A-Z, a-z, 0-9, +, /). It is used in data URLs, email attachments, JWT tokens, and anywhere binary data must travel through text-only channels.

Why do some encoders break emoji and non-English text?

Because the browser btoa() function only handles Latin-1. Text must first be encoded to UTF-8 bytes and then Base64-encoded. This tool does the UTF-8 step correctly, so emoji, Urdu, Arabic, and CJK text all round-trip perfectly.

Is Base64 encryption?

No. Base64 is encoding, not encryption: anyone can decode it instantly. Never use it to hide passwords or secrets; it only changes the representation, not the secrecy.

What does the = padding mean?

Base64 works in 3-byte groups. If the input is not a multiple of 3 bytes, = characters pad the output so its length stays a multiple of 4. One or two padding characters at the end are normal.

Is my text uploaded anywhere?

No. The text you paste is encoded or decoded locally by JavaScript in the page. It is never transmitted, logged or stored, so even sensitive strings are safe to process here.

DEVELOPER TOOLS · FREE ONLINE TOOL

Base64 Encode/Decode

Encode text to Base64 or decode it back, with proper UTF-8 handlingAt some point almost every developer meets a wall of gibberish like eyJhbGciOi and needs to know what it hides. This converter reads and writes base64 in both directions: paste an encoded string to decode, or type text to encode.

✓ Free to use✓ No sign-up✓ Ready in your browser

// BASE64 ENCODE/DECODE · GET STARTED

Use Base64 Encode/Decode

Encode text to Base64 or decode it back, with proper UTF-8 handling

Text to encode (UTF-8 safe)

// BASE64 ENCODE/DECODE · HOW IT WORKS

How to use the Base64 Encode/Decode

Pick a mode

Choose Encode or Decode mode.

Paste input

Paste your text or Base64 string into the box.

Convert and copy

Click convert, then copy the result.

// BASE64 ENCODE/DECODE · ABOUT THIS TOOL

About the Base64 Encode/Decode

Base64 shows up everywhere in development: data URLs, auth headers, email MIME, JWTs and config blobs. This tool encodes and decodes both directions with proper UTF-8 handling, so emoji and non-Latin scripts come through intact.

Decoding is strict: invalid characters and bad padding produce a clear error instead of silent garbage. Everything runs locally in your browser, so your data never touches a server.

Where it helps most

Why it earns its bookmark.

Data URIs

Images and fonts embedded in stylesheets hide as base64 blobs; decoding one tells you exactly what is bundled in the CSS.

API auth headers

Basic authentication headers are username and password through the encoder; hand-building one is the standard way to test a protected API.

Email debugging

Email systems encode attachments and headers the same way, so a garbled message often becomes readable the moment you decode it.

JWT inspection

The middle segment of a JWT is base64url; decoding it reveals the claims in plain JSON.

Using it well

Know what it is and is not.

Encoding, not encryption

Anyone can decode base64 in seconds, so it must never be treated as a way to hide secrets.

Transport job

Its real job is keeping binary data intact across text-only systems like email, JSON bodies, XML and URLs.

Private decoding

Because conversion runs in your browser, a token with session data never leaves your machine.

Base64 Encode/Decode: private by design

The conversion runs entirely in your browser. Nothing is uploaded to a server, no signup needed.

// BASE64 ENCODE/DECODE · COMMON QUESTIONS

Base64 Encode/Decode FAQs

What is base64 encoding actually used for?

Base64 turns binary data into a plain ASCII text string so it can travel through systems that only handle text. You will find it in data URIs that embed images in CSS, Basic-auth headers, email attachments under MIME, XML documents carrying binary payloads, and the header and payload segments of JWT tokens.

Is base64 a type of encryption?

Why does my decoded output show strange characters?

What is the difference between base64 and base64url?

Can I decode just the payload of a JWT here?

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