Base64 Encoder & Decoder
Online — Free & Instant
Encode text, URLs, or files to Base64 format — or decode Base64 strings back to plain text. Instant results, no sign-up, completely private.
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What is Base64 and Why Do You Need It?
Base64 is an essential encoding scheme every developer encounters when working with APIs, emails, and web applications.
Base64 is a binary-to-text encoding scheme that converts binary data into a set of 64 printable ASCII characters. The name comes from the 64 characters used: A–Z, a–z, 0–9, +, and /.
It's used whenever you need to transmit binary data over channels that only support text — like embedding images in HTML without external files, attaching files to emails, or sending binary data through a JSON API.
⚠️ Important: Base64 is encoding, not encryption. Anyone can decode it. Never use Base64 to "hide" sensitive data.
Embed Images in HTML/CSS
Convert images to Base64 data URLs to embed them directly in HTML or CSS without external file requests.
background-image: url("data:image/png;base64,...");HTTP Basic Authentication
HTTP Basic Auth sends credentials as Base64-encoded username:password in the Authorization header.
Authorization: Basic dXNlcm5hbWU6cGFzc3dvcmQ=JSON API Data Transfer
Encode binary files or images as Base64 strings to safely include them in JSON payloads without corruption.
{"image": "iVBORw0KGgo..."}Email Attachments (MIME)
Email protocols use Base64 to encode file attachments and binary content in MIME-formatted messages.
Content-Transfer-Encoding: base64How to Use the Base64 Tool
EEncoding (Text → Base64)
- 1Open the Base64 Encoder/Decoder tool
- 2Select the 'Encode' tab
- 3Paste or type your text in the input field
- 4Click the Encode button
- 5Copy the Base64 output
DDecoding (Base64 → Text)
- 1Open the Base64 Encoder/Decoder tool
- 2Select the 'Decode' tab
- 3Paste your Base64 string in the input field
- 4Click the Decode button
- 5Copy the decoded plain text output
Tool Features
Instant Results
Encode or decode in milliseconds with no loading time.
Fully Private
All processing runs in your browser. Data never leaves your device.
Two-Way Conversion
Encode AND decode in the same tool — switch modes with one click.
File Support
Upload files or images and convert them to Base64 data URLs.
URL-Safe Base64
Option for URL-safe Base64 encoding that replaces + with - and / with _.
No Size Limits
Handle short strings or long documents — no artificial limits.
Frequently Asked Questions
What is Base64 encoding?
Base64 is a binary-to-text encoding scheme that converts binary data into a string of ASCII characters using 64 printable characters (A-Z, a-z, 0-9, +, /). It's commonly used to encode data for transmission over text-based protocols like HTTP, email (MIME), and JSON.
What is Base64 used for?
Base64 is widely used to embed binary data (images, files) in HTML/CSS as data URLs, transmit data in JSON APIs, encode binary content in email attachments (MIME), store binary data in XML, and authenticate with Basic Auth headers in HTTP.
Is Base64 encryption?
No. Base64 is encoding, not encryption. It's a reversible transformation with no secret key. Anyone can decode Base64 data without any password. Do not use Base64 to secure sensitive data — use proper encryption algorithms like AES-256 instead.
How do I encode text to Base64 online?
Open the Base64 Encoder/Decoder tool on WebToolsBox, select 'Encode' mode, paste or type your text in the input field, and click Encode. The Base64 output appears instantly and can be copied with one click.
How do I decode a Base64 string?
Open the Base64 tool, select 'Decode' mode, paste your Base64 string into the input field, and click Decode. The original text or data appears in the output instantly.
Can I encode images to Base64?
Yes. You can upload an image file and the tool will convert it to a Base64 data URL (e.g., data:image/png;base64,...) that you can embed directly in HTML <img> tags or CSS background-image properties.