Base64 Encoder / Decoder
Encode text to Base64 or decode Base64 to text instantly β perfect for APIs, email attachments, and data transmission.
π Related Developer Tools
What is Base64?
Base64 is a binary-to-text encoding scheme that represents binary data in an ASCII string format using a radix-64 representation. It is commonly used to transmit data over media that are designed to handle textual data, such as email attachments (MIME), embedding images in HTML/CSS (data URLs), storing binary data in JSON, and HTTP Basic Authentication.
The Base64 alphabet consists of A-Z, a-z, 0-9, +, /, and the equals sign (=) for padding. Each Base64 character represents 6 bits of data, so the encoded size is approximately 33% larger than the original binary data.
Our Base64 Encoder/Decoder handles both standard Base64 and Unicode characters (UTF-8). All processing happens locally in your browser β your data never leaves your device, ensuring complete privacy and security.
How to Use This Base64 Tool
Step-by-Step Guide
- Enter your text in the input field (plain text or Base64 string)
- Click "Encode to Base64" to convert text to Base64 format
- Click "Decode from Base64" to convert Base64 back to readable text
- Click "Clear" to reset both input and output fields
- Copy the result to your clipboard with one click
π‘ Pro Tips
- Encode sensitive data before sending over text-only protocols
- Decode Base64 strings from API responses to read the actual data
- Use Base64 for embedding images in HTML/CSS (data URLs)
- Base64 is NOT encryption β it's encoding. Anyone can decode it!
- Supports UTF-8 characters (emojis, accented letters, Chinese, etc.)
π‘ Example: "Hello World!" encodes to "SGVsbG8gV29ybGQh". Paste that Base64 and click Decode to get back "Hello World!".
Common Base64 Use Cases
π§ Email Attachments (MIME)
Email protocols (SMTP) are text-based. Base64 encodes binary attachments so they can be sent safely through email servers.
πΌοΈ Data URLs (Images in HTML/CSS)
Embed small images directly in HTML/CSS using data:image/png;base64,... β reduces HTTP requests.
π API Authentication (Basic Auth)
HTTP Basic Authentication encodes "username:password" in Base64 and sends it in the Authorization header.
ποΈ Storing Binary Data in JSON
JSON is text-only. Base64 allows binary data (images, files) to be stored in JSON objects.
π JWT Tokens
JSON Web Tokens (JWTs) use Base64url encoding for their header and payload sections.
π¦ Database BLOB Storage
Some databases store binary data as Base64 strings to avoid encoding issues.
Base64 vs Hex vs Base32 vs ASCII
Base64
6 bits per character β 33% size increase. Most compact text encoding. Best for: email, APIs, images.
Hex (Base16)
4 bits per character β 100% size increase. Human-readable (0-9A-F). Best for: debugging, color codes (#FF00AA).
Base32
5 bits per character β 60% size increase. Case-insensitive. Best for: QR codes, manual entry.
ASCII (Plain)
7 bits per character. Only supports English letters, numbers, basic symbols. Not for binary data.
What Do the "=" Signs Mean? (Base64 Padding Explained)
Base64 encodes data in groups of 3 bytes (24 bits) into 4 characters (6 bits each). When the input length is not a multiple of 3 bytes, padding with "=" characters is added:
- No padding β Input length is multiple of 3 bytes
- One "=" β Input has 1 extra byte (8 bits) β encoded as 2 characters + 2 padding
- Two "==" β Input has 2 extra bytes (16 bits) β encoded as 3 characters + 1 padding
π Example: "Man" (3 bytes) β "TWFu" (no padding). "Ma" (2 bytes) β "TWE=" (one padding). "M" (1 byte) β "TQ==" (two padding).
Frequently Asked Questions
1. Is Base64 the same as encryption?
No β Base64 is encoding, not encryption. Anyone with a Base64 decoder can read the original data. Never use Base64 to protect sensitive information. Use proper encryption (AES, bcrypt) for security.
2. Does this tool support Unicode/UTF-8 characters?
Yes! Our tool correctly handles emojis (π), accented letters (Γ©, ΓΌ, Γ§), Chinese characters (δ½ ε₯½), and all UTF-8 text. Test it with "Hello δΈη π"
3. Why does Base64 make data larger?
Base64 uses 6 bits per character, while raw binary uses 8 bits per byte. 8/6 = 1.33, so Base64 data is approximately 33% larger than the original. This is the trade-off for text-safety.
4. Can I encode files with this tool?
This version handles text input. For file encoding, paste the file's text content or use our file upload feature (coming soon). Large files may cause performance issues.
5. Is my data stored or tracked?
Absolutely not. All encoding/decoding happens entirely within your browser using JavaScript. ToolHub does not store, track, or transmit any data you enter. Complete privacy guaranteed.
6. What's the difference between Base64, Base64url, and Base64 for URLs?
Standard Base64 uses "+" and "/", which have special meanings in URLs. Base64url replaces "+" with "-" and "/" with "_" to make the string safe for URLs. Our tool uses standard Base64.
7. Why do I see an error when decoding?
The most common reasons: incorrect Base64 string (missing characters, wrong alphabet), invalid padding, or non-Base64 characters. Our tool will show an error message explaining the issue.
8. Does this tool work offline?
Yes β once the page loads, the Base64 encoder/decoder works completely offline. No internet connection required for encoding or decoding.
Quick Base64 Reference Examples
"Hello"
Base64: SGVsbG8=
"Base64"
Base64: QmFzZTY0
"admin:admin123"
Base64: YWRtaW46YWRtaW4xMjM=
"https://tool-hub-7.app"
Base64: aHR0cHM6Ly90b29sLWh1Yi03LmFwcA==
"Hello δΈη"
Base64: SGVsbG8g5LiW55WM
"π Smile"
Base64: 8J+YgCBTbWlsZQ==
π Other Developer Tools You Might Need
Developer Note: Base64 is widely used in web development. Use this tool to quickly encode/decode strings for API testing, authentication, and data transmission.