About This Base64 Encoder & Decoder Tool
Our free online Base64 encoder and decoder helps developers, designers, and anyone working with data to encode text into Base64 format and decode Base64 strings back to their original form. Whether you're embedding images in HTML/CSS, transferring data via APIs, or debugging encoded payloads — this tool makes it fast and effortless.
Key Features
- Client-side processing — All encoding and decoding happens in your browser. Your data never leaves your device, ensuring maximum privacy and security.
- Real-time character count — See exactly how much data you're working with as you type.
- Copy & Download — Instantly copy results to clipboard or download as a text file.
- Encode & Decode in one place — Switch between modes with a single click. No need for multiple tools.
- Supports Unicode — Handles emojis, Chinese characters, and all UTF-8 text correctly.
- No sign-up required — Completely free, no registration, no limits.
Common Use Cases
- Data URIs — Encode images to Base64 for embedding directly in HTML or CSS files.
- API Development — Encode authentication credentials (Basic Auth) or binary payloads.
- Email Attachments — Base64 encoding is used in MIME email formats.
- JSON Web Tokens (JWT) — Decode the payload section of JWTs for debugging.
- Database Storage — Encode binary data for storage in text-based databases.
- Debugging — Quickly decode obfuscated or encoded text strings.
Frequently Asked Questions
What is Base64 encoding?
Base64 is a binary-to-text encoding scheme that converts binary data into a sequence of 64 printable ASCII characters (A-Z, a-z, 0-9, +, /). It's commonly used to transmit binary data over text-based protocols like HTTP, SMTP, or to embed binary data in JSON/XML documents. Every 3 bytes of binary data become 4 Base64 characters.
Is my data secure when using this tool?
Yes! This tool performs all encoding and decoding entirely in your browser using JavaScript. No data is ever sent to any server, uploaded, or stored. You can verify this by disconnecting your internet after loading the page — the tool will continue to work offline.
Does this tool support Unicode (Chinese, Emoji, etc.)?
Absolutely. We use the TextEncoder API which properly handles all UTF-8 characters including Chinese, Japanese, Korean, emojis 😊, and special symbols. Older tools that use plain btoa() fail on these characters — ours does not.
What's the maximum file size I can encode?
Since all processing happens in your browser, the limit depends on your device's memory and browser. Most modern browsers handle files up to 50-100MB comfortably. For very large files, we recommend using native command-line tools like base64 on macOS/Linux or certutil on Windows.
Is Base64 encryption?
No! Base64 is encoding, not encryption. It does not provide any security — anyone can decode Base64 data back to its original form. It's designed for data transport and compatibility, not for protecting secrets. If you need to protect sensitive data, use proper encryption like AES.