Free · No Signup · Privacy-First

Professional Base64
Encoder & Decoder

Encode text, files, and images to Base64 — or decode Base64 back to original format. Auto-detection, URL-safe mode, image preview, batch processing, and full encoding control. 100% private, all in-browser.

✦ Auto-Detect Mode ✦ URL-Safe Base64 ✦ File & Image Support ✦ Batch Processing ✦ Image Preview ✦ UTF-8 Encoding
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Encoding:
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💾 Input
📄 Output
Output will appear here...
📷 Image Preview
Options:
💾 Upload File
📄
Drop your file here
or click to browse — images, documents, any binary file
Max 10MB · All processing in-browser
📄 Base64 Output
Upload a file to encode it to Base64...
📷 File Preview
🔘 Decode Base64 to File
Filename:
MIME type:
Operation:
Options:
Result will appear here
Result will appear here
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Compute hashes and validate Base64 strings for data integrity verification.
💾 Input
🔐 Hash Output
Enter text to compute hashes...
✅ Base64 Validation
Ready Encoding: UTF-8
⌫ 100% Local Processing
⚡ Features

Professional-Grade Base64 Processing

Advanced encoding, decoding, and verification tools for developers and security professionals.

⚡

Auto-Detection

Intelligently detects whether your input is plain text or Base64, automatically choosing encode or decode. No manual mode switching required.

🔗

URL-Safe Base64

Replace + with - and / with _ for URL and filename-safe encoding. Optionally strip padding characters for clean URLs and tokens.

📄

File Encoding

Upload and encode images, documents, and binary files to Base64. Decode Base64 strings back to downloadable files with MIME type detection.

📷

Image Preview

Instantly preview decoded images including PNG, JPEG, GIF, WebP, SVG, and BMP. See dimensions, file size, and MIME type information.

📋

Batch Processing

Encode or decode multiple strings simultaneously. Add unlimited entries, process all at once, and copy all results with a single click.

🔐

Hash & Validate

Compute SHA-256, SHA-1, and MD5 hashes of text or Base64 data. Validate Base64 strings for correctness with detailed error reporting.

🌐

Encoding Support

Full UTF-8 support with options for ASCII, ISO-8859-1, and Windows-1252. Handles multi-byte characters and Unicode without data loss.

📎

Data URI Output

Generate complete data URI strings for direct embedding in HTML, CSS, or markdown. Includes proper MIME type and base64 prefix formatting.

🔒

100% Private

All encoding and decoding happens locally in your browser. Your data is never sent to any server, ensuring complete privacy and security.

❓ FAQ

Frequently Asked Questions

Paste your text into the input field and click Encode, or enable Auto-Detect mode which will automatically encode plain text. The Base64 output appears instantly in the output panel. You can also use the keyboard shortcut Ctrl+Enter to process.
URL-safe Base64 replaces the + character with - and the / character with _, making the encoded string safe for use in URLs, query parameters, and filenames. It also optionally removes the = padding characters. This is essential for JWT tokens, data URLs, and API parameters.
Yes, switch to the File Encode/Decode tab and upload any image file. The tool encodes it to Base64 and can generate a data URI string for embedding directly in HTML img tags or CSS backgrounds. You can also preview decoded images and download them.
Absolutely. All encoding, decoding, and file processing happens entirely within your browser using JavaScript. No data is ever transmitted to any server. Your files and text remain completely private and are processed locally on your device.
The tool supports files up to 10MB for encoding. For larger files, browser memory limitations may apply. Base64 encoding increases file size by approximately 33%, so a 10MB file produces roughly 13.3MB of Base64 output. All processing uses efficient ArrayBuffer operations for optimal performance.
The auto-detection algorithm analyzes your input by checking if it matches valid Base64 character patterns (A-Z, a-z, 0-9, +, /, =), proper length, and valid padding. If the input appears to be Base64, it decodes it; otherwise, it encodes it. You can always override by manually selecting Encode or Decode mode.