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Base64 Encode & Decode - Base64 Converter Online

Plain Text
Base64 Encoded

About the Base64 Encoder and Decoder

Base64 encoding is one of the most common operations in web development. It appears in email attachments (MIME encoding), data URIs for inline images, HTTP Basic authentication headers, and anywhere binary data needs to travel through a text-only channel. This tool lets you encode plain text to Base64 or decode a Base64 string back to its original content in a single step.

The encoder and decoder both run in your browser using the native Web API, so performance is excellent and no data is ever sent to a server. This makes the tool safe for encoding sensitive information like API keys or tokens.

How to Use the Base64 Tool

To encode, type or paste your plain text into the input area and select the "Encode" mode. The Base64 output appears instantly. To decode, switch to "Decode" mode and paste a Base64 string. The tool will reveal the original text. If the input is not valid Base64, a clear error message is displayed. Click the copy button to grab the result for use in your code, API request, or configuration file.

Features

  • Encode and decode. Toggle between encoding and decoding with a single click.
  • Full UTF-8 support. Correctly handles multi-byte characters including emoji and non-Latin scripts.
  • Instant output. Results appear in real time as you type or paste.
  • Error handling. Malformed Base64 input triggers a helpful error message instead of garbled output.
  • Privacy guaranteed. All processing is client-side; your data never touches a server.

Common Use Cases

Front-end developers use Base64 to embed small images and fonts as data URIs in CSS or HTML, eliminating extra HTTP requests. Backend developers encode credentials for HTTP Basic Auth headers. DevOps engineers decode Base64 secrets stored in Kubernetes manifests or CI/CD environment variables. And anyone inspecting email source code encounters Base64-encoded MIME parts that need decoding. A reliable Base64 tool on hand covers all of these cases.

Frequently Asked Questions

What is Base64 encoding?
Base64 is a binary-to-text encoding scheme that represents binary data using a set of 64 ASCII characters (A-Z, a-z, 0-9, +, /). It is commonly used to embed binary data in text-based formats like JSON, XML, HTML, email (MIME), and data URIs.
Is Base64 encryption?
No. Base64 is an encoding, not encryption. It does not protect data; anyone can decode a Base64 string. Its purpose is to safely transport binary data through text-only channels, not to provide confidentiality.
Why does Base64 make data larger?
Base64 encoding increases the size of data by approximately 33%. This is because every 3 bytes of input are represented as 4 Base64 characters. The overhead is an accepted trade-off for the ability to embed binary content in text formats.
Does this tool support UTF-8 text?
Yes. The encoder properly handles UTF-8 multi-byte characters, including accented letters, CJK characters, and emoji. The text is first encoded to UTF-8 bytes, then those bytes are Base64-encoded.
What is the difference between standard Base64 and URL-safe Base64?
Standard Base64 uses '+' and '/' as two of its 64 characters, plus '=' for padding. URL-safe Base64 replaces these with '-' and '_' and often omits padding. URL-safe encoding is required in contexts like JWTs and data URIs where '+', '/', and '=' have special meaning.