Converter
Base64 Encoder / Decoder
Convert plain text to Base64, or decode Base64 back into readable text.
About Base64 encoding and common questions
What is Base64?
Overview
Base64 is an encoding method that converts data into a text-safe format. It represents information using a limited set of characters that can be safely copied, stored, or transferred through text-based systems.
Base64 is commonly used when binary data or special characters need to be included inside formats that expect plain text.
Where it is used
- API requests and responses
- JSON payloads
- Email attachments and MIME messages
- Data URLs for small images or files
- Configuration files
- Testing and debugging encoded values
Key facts
- Base64 is encoding, not encryption.
- Base64 output is usually larger than the original input.
- Base64 text may end with padding characters such as = or ==.
- A valid Base64 value can usually be decoded back to the original data.
Examples
Simple Base64 encoding
A short text value can be encoded into a Base64 string and later decoded back.
Hello worldSGVsbG8gd29ybGQ=Base64 is not encryption
The encoded value looks different, but it can still be easily decoded by anyone.
c2VjcmV0secretCommon mistakes
- Treating Base64 as a secure way to hide sensitive information.
- Assuming Base64 and encryption are the same thing.
- Removing padding characters when another system expects standard Base64 format.
- Trying to use Base64 for very large files when normal file upload is more appropriate.
Limitations
- Base64 increases the size of the original data.
- Decoded binary data may not always appear as readable text.
- Different systems may expect standard Base64 or URL-safe Base64.
Technical details
Base64 padding
Padding characters are used when the original data length does not fit evenly into Base64 groups. This is why some Base64 strings end with one or two equals signs.
Encoding vs encryption
Encoding changes the representation of data. Encryption protects data using a secret key. Base64 does not provide security by itself.
Frequently asked questions
Is Base64 encryption?
No. Base64 is encoding, not encryption. Anyone who has the encoded value can decode it.
Why does Base64 output look longer than the original text?
Base64 uses a text-safe representation, which usually increases the size of the original data.
Why does Base64 sometimes end with equals signs?
Equals signs are padding characters. They help complete the encoded output when the original data length does not divide evenly.
Can Base64 always be decoded?
A valid Base64 value can usually be decoded, but the result may be binary data rather than readable text.
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Plain text
Base64
Guide
How to use the Base64 Encoder / Decoder
Use this tool to quickly encode plain text into Base64 or decode a Base64 string back into readable text.
Encode text to Base64
Choose encode mode, paste your plain text into the input field, and generate a Base64 version that can be copied and reused.
Decode Base64 to text
Switch to decode mode, paste a Base64 string, and convert it back into readable plain text.
Common use cases
Base64 is often used when text or binary data needs to be represented safely in formats such as JSON, URLs, configuration files, or API payloads.
Browser-based conversion
The converter is designed for quick everyday encoding and decoding tasks directly in your browser.