 Base64 Encoder

The Base64 Encoder converts between plain text and Base64-encoded strings. It supports both standard Base64 and URL-safe Base64Url encoding, multiple text encodings, and file import/export of binary data.

:::info Screenshot needed — light/dark 📸 base64-encoder-light.png and base64-encoder-dark.png — Full Base64 Encoder view with text in left pane and encoded output in right pane :::

Interface

The tool has a two-pane layout:

• Left pane — Text (plain text input or decoded output)
• Center buttons — Encode () and Decode ()
• Right pane — Base64 Encoded (Base64 output or encoded input)
• A vertical splitter lets you resize the panes

Toolbar

Control	Icon	Description
Load from File		Open any file and encode its binary contents to Base64
Save to File		Decode the Base64 text and save the raw bytes to a file
Encoding Algorithm:	—	Base64 (standard, with line breaks) or Base64Url (URL-safe)
Text Encoding:	—	Character encoding used when converting between text and bytes

Supported Text Encodings

Encoding	Description
UTF-8	Default; covers all Unicode characters
UTF-16	Unicode, 2 bytes per character (little-endian)
UTF-32	Unicode, 4 bytes per character
ASCII	7-bit US-ASCII
Latin1	ISO-8859-1 (Western European)
BigEndianUnicode	UTF-16 big-endian

Encoding Text

1. Type or paste text in the left pane (Text)
2. Select the Encoding Algorithm: and Text Encoding: from the toolbar
3. Click Encode ()
4. The Base64 string appears in the right pane (Base64 Encoded)

Decoding Text

1. Paste the Base64 string in the right pane (Base64 Encoded)
2. Click Decode ()
3. The decoded text appears in the left pane (Text)

You can also paste Base64 in the left pane and decode it — the resulting original text will overwrite the left pane content.

Working with Files

Load from File reads a binary file from disk, encodes it to Base64 (respecting the selected algorithm), and places the result in the right pane. This works for any file type — images, PDFs, certificates, etc.

Save to File decodes the Base64 content from the right pane and writes the raw bytes to a file. After saving, an info bar offers shortcuts to Open File and Open Container folder for the saved file.

Base64Url Mode

Selecting Base64Url changes behavior:

• Uses URL-safe characters (- and _ instead of + and /)
• Produces padding-free output
• The right pane enables word-wrap for easier reading of long URL-safe tokens

Base64Url is commonly used for JWT tokens, OAuth2 state parameters, and other URL-embedded Base64 data.

Error Handling

If encoding or decoding fails (e.g., invalid Base64 input), an error info bar appears at the bottom with the specific error message. The bar is dismissible.

See Also

• JWT Utility — uses Base64Url encoding for token parts