Base64 Encoder / Decoder

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

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What is this tool? Base64 Encoder / Decoder?

Encode text to Base64 online or decode Base64 strings back to plain text, instantly, for free, with no signup required. Base64 is an encoding scheme that converts binary or text data into a portable string of ASCII characters. It is widely used to embed images inline in HTML and CSS (data URIs), transmit binary data in JSON payloads, encode email attachments (MIME), pass data safely in URLs, and store binary data in text-based systems like databases and configuration files.

How do you use this tool? Base64 Encoder / Decoder

  1. Choose a mode: Encode (text → Base64) or Decode (Base64 → text).
  2. Type or paste your input text into the left area.
  3. The output updates automatically, or click the Encode/Decode button.
  4. Click Copy to copy the output, or use the Swap button to flip input and output.

Common Use Cases

Inspect encoded API values

Decode tokens, payload fragments, or configuration values to confirm what text was encoded, provided the content is not encrypted.

Embed small assets

Convert small images or fonts into data-URL payloads when an inline asset is appropriate and the size overhead is acceptable.

Prepare Basic authentication values

Encode the username and password portion required by HTTP Basic authentication during local testing.

Move binary-safe text through text-only systems

Represent bytes using printable ASCII characters when a transport cannot safely carry arbitrary binary data.

Why is this tool useful?

Immediate round-trip testing

Encode text, decode the result, and verify that the original content survives unchanged.

Clear UTF-8 handling

A browser tool can expose encoding problems with accents, emoji, and non-Latin characters before the value reaches an API.

No command-line setup

Inspect short Base64 values quickly without writing a script or installing a utility.

Best Practices

  • ✓ Remember that Base64 is encoding, not encryption. Anyone with the value can decode it without a key.
  • ✓ Confirm whether the destination expects standard Base64 or URL-safe Base64, because the alphabet and padding rules can differ.
  • ✓ Use UTF-8 consistently before encoding text so accented characters and emoji round-trip correctly.
  • ✓ Avoid embedding large files as Base64 in JSON or HTML. The encoded value is roughly one-third larger than the original bytes.
  • ✓ Remove surrounding quotes, whitespace, or data-URL prefixes only when the receiving system expects the raw Base64 payload.

Practical examples

Encode plain text
Input
Hello, ManyUtils!
Output
SGVsbG8sIE1hbnlVdGlscyE=
Decode a Base64 value
Input
eyJzdGF0dXMiOiJvayJ9
Output
{"status":"ok"}

Frequently Asked Questions

Base64 converts data into a string using 64 safe ASCII characters (A,Z, a,z, 0,9, +, /). It increases data size by about 33% but makes binary data safe to transmit in text-based protocols.

No. Base64 is an encoding scheme, not encryption. It does not provide any security. Anyone can decode a Base64 string without a key. Never use Base64 to hide sensitive data.

The = characters are padding. Base64 encodes data in 3-byte chunks. If the input length isn't a multiple of 3, padding characters are added to ensure the output length is a multiple of 4.

Standard Base64 uses + and / which have special meanings in URLs. URL-safe Base64 replaces these with - and _ so the encoded string can be safely used in URLs and filenames.

To encode a binary file (like an image) to Base64, you would need to read the file as binary data first. This tool handles text-to-Base64 encoding. For binary files, use a file-upload Base64 tool or a command like: base64 -i image.png on macOS/Linux.

No. The tool creates a new result in the browser. Your original remains unchanged unless you overwrite it after downloading.

Related Guides

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