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Base64 Encoder & Decoder

Encode, decode, and inspect Base64 payloads with URL-safe mode, line-break control, drag-and-drop input, and instant validation — all in your browser.

Text Input

Syntax: text

Base64 Output

Output will appear here

How It Works

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Input Text or Base64 Data

Paste text to encode or Base64 string to decode into our online Base64 encoder. Support for large text files, binary data, JSON objects, API keys, and any text content. Our Base64 tool handles both standard and URL-safe encoding formats for maximum compatibility.

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Configure Base64 Options

Choose between encode or decode mode, enable URL-safe Base64 encoding for URLs and filenames, add line breaks for better readability, and customize padding options. Our Base64 encoder offers both standard RFC 3548 and URL-safe RFC 4648 encoding variants.

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Encode or Decode Instantly

Click 'Encode' to convert text to Base64 or 'Decode' to convert Base64 back to text. Our Base64 converter processes data locally in your browser with no server uploads required. Get instant results with real-time conversion and error detection.

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Copy or Download Results

Copy encoded/decoded results to clipboard with one click, download as text files, or share Base64 strings directly. Perfect for data URIs, embedding images in CSS/HTML, API authentication tokens, and secure data transmission over text protocols.

Problems It Solves

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Problem

Manual Base64 conversion is error-prone, especially when working with long payloads, binary files, or JSON blobs that need reliable encoding before transmission.

Solution

Encode large payloads instantly with drag-and-drop file support, automatic size reporting, and line-break options. The tool processes everything locally so sensitive data never leaves your browser.

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Problem

Decoding Base64 strings that arrive malformed or URL-safe encoded can lead to confusing errors and unreadable output.

Solution

Automatic cleanup converts URL-safe characters, repairs padding, and flags invalid characters with clear validation errors so you can correct issues before consuming the data.

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Problem

Developers often need insight into payload sizes and encoding behavior to meet platform limits or diagnose downstream failures.

Solution

Detailed metadata shows original vs. encoded length, compression overhead, padding usage, and encoding mode so you can document or troubleshoot integrations quickly.

Why Choose This Tool

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Privacy-First Conversion

All encoding and decoding happens in the browser — no uploads, no logging. Safely process API keys, credentials, or binary blobs without leaving your machine.

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Flexible Encoding Controls

Toggle URL-safe mode, add line breaks, or switch between encode/decode workflows instantly. The tool respects RFC 4648 defaults while giving you precise control over output.

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Developer-Centric UX

Paste, drag files, copy results, download text, or store past runs in tool history. The streamlined interface keeps repetitive encoding tasks fast for busy engineers.

Frequently Asked Questions

What is Base64 encoding?
Base64 is a binary-to-text encoding scheme that represents binary data in ASCII string format by translating it into a radix-64 representation.
When should I use URL-safe Base64?
Use URL-safe Base64 when the encoded string will be used in URLs or filenames. It replaces + with - and / with _, and removes padding.
Is Base64 encryption?
No, Base64 is encoding, not encryption. It's easily reversible and provides no security. Use proper encryption for sensitive data.
Why is my Base64 string longer than the original?
Base64 encoding increases size by approximately 33% because it uses more characters to represent the same data.
How do I encode text to Base64 online?
Simply paste your text into the input field and click "Encode". Our Base64 encoder supports all text formats including UTF-8, special characters, and multi-language content.
Can I decode Base64 strings with this tool?
Yes, switch to "Decode" mode to convert Base64 strings back to readable text. The tool automatically detects and handles both standard and URL-safe Base64 formats.
What's the difference between Base64 and Base64 URL-safe?
Standard Base64 uses +, /, and = characters. URL-safe Base64 replaces + with -, / with _, and removes padding (=) to safely include in URLs without encoding conflicts.
Can I encode files to Base64?
Yes, drag and drop files or use the file picker to encode any file type to Base64. Perfect for embedding images in CSS/HTML or creating data URIs for web development.
How do I create a data URI from an image?
Upload your image file and the tool will generate a complete data URI with the correct MIME type, like "data:image/png;base64,..." ready for HTML img tags or CSS backgrounds.
Is Base64 encoding secure for passwords?
No, Base64 is not secure for passwords. It's easily decoded by anyone. Use proper password hashing algorithms like bcrypt, Argon2, or PBKDF2 for password security.
Why do I see padding characters (=) in Base64?
Padding characters (=) are added to make the Base64 string length a multiple of 4. They indicate the original data length and ensure proper decoding.
Can I encode binary data to Base64?
Absolutely! Base64 is specifically designed for encoding binary data into text format. Upload any binary file and get a Base64 representation that's safe for text-based protocols.
How large files can I encode to Base64?
The tool can handle files up to 10MB efficiently. Remember that Base64 encoding increases file size by ~33%, so a 10MB file becomes ~13MB when encoded.
What are common uses for Base64 encoding?
Email attachments (MIME), embedding images in HTML/CSS, API tokens, configuration files, database blob storage, and transmitting binary data over text protocols like JSON or XML.

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