Base64 Encoder / Decoder

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🔐 Base64 Encoder / Decoder

Encode plain text to Base64 or decode Base64 back to plain text.

Output

What is Base64 Encode / Decode?

Base64 is a binary-to-text encoding scheme that represents binary data in an ASCII string format. It converts arbitrary bytes into a set of 64 printable characters (A–Z, a–z, 0–9, +, /). This makes it possible to safely transmit data over text-only channels such as email (MIME), JSON APIs, and HTML attributes without corruption from control characters.

Common real-world uses include embedding images directly in HTML or CSS as data URLs, storing binary data in JSON payloads, encoding credentials in HTTP Basic Authentication headers, and transmitting email attachments. Developers also use Base64 when they need to store binary blobs in databases that only accept text. Decoding reverses the process — useful when you receive a Base64 string and need the original content.

How to Use the Base64 Encoder / Decoder

  1. Paste your plain text (or Base64 string) into the input box.
  2. Click Encode to Base64 to convert plain text → Base64.
  3. Click Decode from Base64 to convert Base64 → plain text.
  4. Use Swap to move the output back to the input for chaining operations, then click Copy to copy the result.

Why Use Our Base64 Tool?

  • 100% Free — No fees, no limits on input size.
  • No Registration — No sign-up required.
  • Browser-Based — Your text is processed locally using the native btoa() / atob() API — nothing is sent to a server.
  • Unicode Support — Correctly handles multi-byte UTF-8 characters including emoji and non-Latin scripts.
  • Instant Swap — Quickly flip output back to input for decode-after-encode workflows.

Frequently Asked Questions

No. Base64 is encoding, not encryption. It is fully reversible by anyone without a key. Do not use it to protect sensitive data — use proper encryption like AES-256 for that. Base64 is designed for safe data transport, not secrecy.

Base64 encodes every 3 bytes into 4 characters. When the input length is not a multiple of 3, padding characters (=) are appended to make the output length a multiple of 4. One = means one byte of padding; == means two bytes.

Use our Image to Base64 tool to get the data URL, then embed it like this: <img src="data:image/png;base64,iVBOR...">. This eliminates an HTTP request for the image but increases HTML file size.

Common causes include: missing or extra padding (= characters), line breaks or spaces inserted by email clients, or URL-safe Base64 (uses - and _ instead of + and /). Remove whitespace and replace - with + and _ with / before decoding.

Quick Facts

  • ✓ 100% free, no hidden fees
  • ✓ No account or login needed
  • ✓ Works in any browser
  • ✓ Your data never leaves your device
  • ✓ Full Unicode / UTF-8 support