Base64 Encode / Decode

Key takeaways

• UTF-8 safe encode and decode
• Runs fully client-side
• Not encryption - reversible by design
• Intent pages cover text, JSON, HTML, and URL use cases

What is Base64?

Base64 encodes binary or text as ASCII using 64 characters so data can travel in text-only channels.

Anyone can decode Base64. Use it for transport and embedding (JSON, email, data URLs), not for secrecy. This tool uses UTF-8 for text round-trips.

Features

• UTF-8 safe

  Correctly encodes and decodes Unicode text, not just ASCII.

• Encode & decode

  One workspace for both directions with clear primary actions.

• Data URL friendly

  Paste a data:...;base64,... value and decode the payload.

• Copy & download

  Move results into tickets, configs, or editors in one click.

How it works

1. 1

   Paste text or Base64

   Use plain text for Encode, or a Base64 string for Decode.

2. 2

   Choose Encode or Decode

   Encode produces Base64. Decode restores UTF-8 text.

3. 3

   Copy the result

   Copy or download the output for use in code or payloads.

Example walkthroughs

• Hello World

  Encode produces SGVsbG8sIFdvcmxkIQ==.

  Hello, World!

• Unicode

  UTF-8 bytes are Base64-encoded without mojibake.

  café ☕

Use cases

• Embed secrets in configs

  Encode short tokens or keys for YAML/JSON configuration files.

• Inspect data URLs

  Decode Base64 segments from data URLs or API responses.

• Debug JWT segments

  Pair with JWT Decode when you need raw Base64URL inspection.

Code snippets

• UTF-8 Base64 in the browser

  js

  This tool uses the same UTF-8 → Base64 approach for Unicode text.

  const bytes = new TextEncoder().encode(text);
  const b64 = btoa(String.fromCharCode(...bytes));

Common errors

• Invalid character in decode

  Cause: The string includes spaces, newlines, or non-Base64 characters.

  Fix: Strip whitespace or paste a clean Base64 / data-URL payload.

• Mojibake after decode

  Cause: The original bytes were not UTF-8 text (or were Latin-1 treated as UTF-8).

  Fix: Confirm the source encoding; this decoder emits UTF-8 text.

About Base64 Encode / Decode

Base64 Encode / Decode converts between plain UTF-8 text and Base64 so you can embed binary-safe payloads in JSON, APIs, emails, and data URLs. Use it whenever a channel only accepts ASCII or mangles raw binary and Unicode.

Base64 is encoding, not encryption - anyone can decode the result. Prefer it for transport and embedding, not for secrecy. This workspace uses UTF-8 for text round-trips and can decode data:...;base64,... payloads when you paste a full data URL.

Encoding and decoding run entirely in your browser. Draft notes, tokens wrapped for transport, and internal IDs never need to hit a remote encoder. Intent pages cover text-, JSON-, HTML-, and URL-specific workflows when search intent is more specific than the general tool.

Best practice: decode and inspect before trusting opaque fields. For query parameters that must remain readable URLs, use URL Encode instead of Base64 of a whole link. For JWT inspection, decode the token with JWT Decode rather than treating the middle segment as ordinary Base64 text alone.

Frequently asked questions

Explore more

• All developer tools

  Browse formatters, converters, encoders, and more.

• Encoding tools

  Base64, URL encode/decode, HTML entities, and related utilities.