Encoding Tool

Base64 Encoder / Decoder

Encode or decode Base64 strings instantly. Supports standard, URL-safe, file encoding, JWT decoding and more 100% private, runs in your browser.

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Mode

Variant

Output Wrap

Quick Load Samples

Plain Text

0chars

0 Bsize

Base64 Output

Your encoded Base64 will appear here…

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100% Private

All encoding and decoding runs entirely in your browser. No data is ever sent to any server.

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Instant Results

Output updates in real-time as you type. No button clicks needed for live encoding.

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File Encoding

Upload any file up to 5MB and get its Base64 representation instantly for data URIs.

What is Base64 & When Do You Use It?

🖼️

Inline Images

Embed images directly in HTML/CSS as data URIs no separate HTTP request needed.

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JWT Tokens

JSON Web Tokens use Base64URL encoding for the header and payload sections.

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Email Attachments

MIME email standard uses Base64 to encode binary attachments as text.

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API Authentication

HTTP Basic Auth sends credentials as Base64-encoded username:password strings.

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Binary Data Transfer

Transfer binary data safely through text-only channels like JSON APIs.

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URL-Safe Variant

Base64URL replaces + with - and / with _ for safe use in URLs and filenames.

Standard vs URL-Safe Base64

Standard Base64

Spec: RFC 4648

Chars: A–Z, a–z, 0–9, +, /, =

Use: General encoding, email, data URIs

URL-Safe Base64

Spec: RFC 4648 §5

Chars: A–Z, a–z, 0–9, -, _, no padding

Use: JWT tokens, URLs, filenames, cookies