Base64 Decoder

Decode Base64 strings back to readable text.

A Base64 decoder converts a Base64 string back into its original text, reversing the encoding process.

How to Use the Base64 Decoder

  1. Paste Base64. Enter the Base64 string to decode.
  2. Copy the result. Get the decoded text.

This tool processes your input locally in your browser. Nothing is uploaded.

What Is Base64 Decoder?

Decoding Base64 lets you read data that was encoded for transmission, such as tokens, data URIs and embedded payloads.

How decoding works

The decoder reverses the Base64 mapping, converting the 64-character alphabet back into the original bytes, then decodes UTF-8 text.

Key Features

  • Decodes UTF-8 correctly
  • Clear invalid-input errors
  • Local processing

Examples

  • "SGVsbG8sIFdvcmxkIQ==" decodes to "Hello, World!".

Common Use Cases

  • Reading tokens
  • Extracting data URIs
  • Inspecting payloads

Tips & Best Practices

  • Only decode Base64 you trust; it may contain executable data.

Limitations

  • Invalid padding or characters produce an error.

Related Tools

Base64 Encoder Encode text to Base64 for data transmission. Developer Use Tool →
URL Decoder Decode percent-encoded URLs and query strings. Developer Use Tool →
HTML Entities Decode Decode HTML entities back into readable characters. Developer Use Tool →

Related Articles

Base64 Decoder – Complete Guide & Free Online Tool A Base64 decoder converts a Base64 string back into its original text, reversing the encoding process. Free online tool included. Read guide → URL Encoder – Complete Guide & Free Online Tool A URL encoder converts special characters into percent-encoded sequences so text can be safely placed in URLs and query parameters. Free online tool included. Read guide → HTML Entities Encode – Complete Guide & Free Online Tool An HTML entities encoder converts characters like <, >, & and " into their entity codes, so they render as plain text instead of markup. Free online tool included. Read guide → Hash Generator – Complete Guide & Free Online Tool A hash generator computes a fixed-size hash of your text using algorithms like SHA-256, useful for checksums and integrity verification. Free online tool included. Read guide →

Frequently Asked Questions

What does a Base64 decoder do?
It converts a Base64 string back into its original text.
Why is decoding useful?
To read data that was Base64-encoded for safe transmission.
Is it free?
Yes, and it runs locally.

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