Can I encode files to Base64?

This tool is for text encoding. For file - to - Base64 conversion, we may add a dedicated tool in the future.

What's the maximum text length?

There's no strict limit, but very large texts may affect browser performance. We recommend keeping input under 1MB for stable performance.

Does this work offline?

Yes, once the page is loaded, the tool works entirely in your browser without needing an internet connection.

Base64 Encoder/Decoder - Online Base64 Tool

All processing happens in your browser. Your data is never sent to our servers.

Base64 is commonly used for tokens, basic auth, data URLs, and API payloads, but decoding/encoding by hand is error - prone and hard to verify.

Encode text to Base64 or decode Base64 back to text instantly. Supports UTF - 8, Unicode, and special characters.

Show detailed guide & explanations▼

Why you may need this tool

Base64 strings appear in authentication headers, tokens, data URLs, and configuration values. They are compact and transport - friendly, but they are not human - readable. During debugging, you often need to confirm what a Base64 value actually contains, whether it is valid, and whether the decoded output is text or binary. An encoder/decoder helps you verify values quickly and avoid mistakes with padding, character sets, and copy/paste edits.

How to use

Paste the input, choose encode or decode, and verify the output matches what you expect before using it elsewhere.

Paste your text or Base64 string in the input area
Click 'Encode' to convert text to Base64
Or click 'Decode' to convert Base64 back to text
Copy the result

Examples

Verifying what a Base64 token segment contains

Logs or configs may contain Base64 segments that you need to interpret. Decoding lets you confirm the original text and spot encoding mistakes early.

Creating Base64 test values for configuration

Some systems require Base64 for certain fields or fixtures. Encoding a known input and decoding it back is a practical way to validate your test data.

Benefits & differentiators

Encoding and decoding becomes a repeatable check instead of guesswork. This helps when you troubleshoot request headers, inspect data URLs, or verify test fixtures. It also highlights an important safety point: Base64 is an encoding, not encryption. If the content is sensitive, you should treat the Base64 string as potentially recoverable data and handle it accordingly.

Who this is for

Recommended if you: - debug headers, tokens, and payloads with Base64 fields - validate that decoded output is correct text - prepare Base64 values for tests or configuration - want a quick sanity check for padding and character issues

FAQ

What is Base64 encoding?

Base64 is a way to encode binary data as ASCII text. It's commonly used for embedding images in HTML/CSS, sending data in URLs, and API authentication.

Does this support Unicode and special characters?

Yes, we fully support UTF - 8 encoding, which includes emoji, Korean, Japanese, Chinese, and all special characters.

Is my data uploaded to your servers?

No. All encoding and decoding happens locally in your browser. Your data never leaves your device.

Why does decoding sometimes fail?

Decoding fails if the input isn't valid Base64, has incorrect padding, or the decoded bytes aren't valid UTF - 8 text. Check your input for errors.

Is this Base64 URL - safe?

This tool uses standard Base64 encoding. For URL - safe Base64 (Base64URL), you would need to replace '+' with ' - ' and '/' with '_'.