Encode and decode Base64 strings directly in your browser. No data is sent to the server. This tool is useful for system administrators, developers, and everyday troubleshooting tasks.
How to use
- Paste the text you want to encode or decode
- Click the appropriate action
- Copy the generated output
Frequently asked questions
Base64 is a binary-to-text encoding scheme that represents binary data using 64 printable ASCII characters: A–Z, a–z, 0–9, and the symbols + and /.
It is commonly used to safely transmit binary data over channels that only support text, such as email, JSON APIs, and HTML data attributes. Base64 does not encrypt data — it only encodes it.
Base64 encoding is used in many everyday IT tasks:
- Embedding images in HTML or CSS as
data:URIs - Encoding credentials in HTTP Basic Authentication headers
- Passing binary data in JSON API payloads
- Encoding email attachments in MIME format
- Storing binary values in configuration files or environment variables
Paste your plain text into the Input field above and click Encode. The Base64-encoded result will appear in the Output field. Click Copy output to copy it to your clipboard.
Encoding is performed entirely in your browser. No data is sent to the server.
Paste the Base64 string into the Input field and click Decode. The decoded plain text will appear in the Output field.
Valid Base64 strings only contain characters A–Z, a–z, 0–9, +, /, and = as padding. If the input is invalid, the tool will show an error.
No. Base64 encoding increases the size of data by approximately 33%. Every 3 bytes of input become 4 Base64 characters.
Base64 is designed for safe text transmission, not compression. If you need to reduce file size, use a compression format such as gzip or zip before encoding.
No. Base64 is encoding, not encryption. Anyone can decode a Base64 string without a key or password. It provides no confidentiality or security.
If you need to protect data, use proper encryption such as AES. Base64 is only useful for format conversion — making binary data safe to transmit as text.
Related guides
certutil -encode and -decode: Base64 encoding files from the Windows command line
Base64 encoding in PowerShell: encode and decode files and strings