Base64 Encoder/Decoder
Encode text to Base64 or decode Base64 to text instantly
Base64 Encoder & Decoder
Encode text or files to Base64, or decode Base64 back to readable text. Supports file encoding for images, documents, and more.
A Base64 encoder converts binary data into text format that appears in more places than most people realize. Email attachments use it for MIME transmission. Data URIs in CSS and HTML rely on it for embedding images directly into code. API authentication headers are often Base64 encoded. Database systems store binary data as Base64 strings for compatibility with text-based storage formats.
Base64 works by converting binary data into a string of ASCII characters using a sixty-four-character alphabet. Each group of three bytes of binary data is represented as four characters in the encoded output. The result is text that can be safely transmitted through systems designed to handle only text, such as email protocols and JSON APIs. When you need to Base64 encode text or files, the process is straightforward.
Web developers embed small images as data URIs to reduce the number of HTTP requests required to load a page. Instead of making a a separate request for each image, the image data is included directly in the HTML or CSS file. This reduces latency for small assets and simplifies deployment for single-file applications.
API developers encode binary payloads for transmission through JSON-based APIs that cannot handle raw binary data. File submission endpoints often accept Base64-encoded content as an alternative to multipart form data. This simplifies the client-side code and ensures compatibility across different programming languages and platforms. A Base64 decoder reverses the process when data needs to be read.
Security researchers decode Base64 tokens and JWT tokens to inspect their contents during vulnerability assessments. The encoded format obscures the data at a glance but provides no actual security, as anyone can decode it without a key. Understanding what is stored in tokens helps identify information leakage and implementation flaws.
Email developers test MIME encoding during the development of email templates and sending systems. Attachments are converted to Base64 and inserted into the email body with appropriate Content-Transfer-Encoding headers. Verifying that the encoding and decoding process preserves file integrity is essential for reliable email delivery.
System administrators decode configuration values stored in Base64 format. Many deployment tools and container orchestration systems store secrets and configuration as Base64 strings. Decoding them for inspection or modification is a routine operational task that requires quick access to a reliable decoder. The ability to encode to Base64 and decode back is essential for these workflows.
The file encoding feature allows encoding of images, PDFs, documents, and other binary files. The complete Base64 string is displayed, along with the data URI prefix that includes the MIME type for direct use in HTML and CSS. The character count of the encoded output is shown so developers can verify that the full file was processed.
Key Features
Text & File Encoding
Encode any text string to Base64, or add a file such as an image, PDF, or document and get its Base64 representation.
Decode to Original
Paste any Base64 string and decode it back to the original text. For file data, download the decoded file directly.
File Preview
When an image is added, the tool shows a preview of the encoded data. See thumbnails before downloading.
Encode & Decode
Choose Mode
Select Encode to convert text or files to Base64, or Decode to convert Base64 back to the original content.
Enter Input
Type text, paste a Base64 string, or add a file. The tool processes the input and displays the result.
Copy or Download
Copy the encoded string to the clipboard or download the decoded file to your machine.
Encoding Tips
- Data URIs include MIME type information: When encoding images, the tool outputs the full data URI including the MIME type prefix, which is what HTML and CSS require for embedding.
- File size increases by about thirty-three percent: Base64 encoding adds overhead. A one-megabyte file becomes roughly one point three three megabytes as Base64. Use it only for small assets in data URIs.
- Base64 is encoding, not encryption: Anyone with the encoded string can decode it instantly without a key. Never use Base64 to protect sensitive information.