Build data URL

Build a data URL from a media type and inline text or Base64 bytes.

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ToolData URL Builder
Input
Output
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Preview

How it works

Media type, parameters, and percent-encoded text or Base64 payload are joined after data:. The comma separates metadata from data, and Base64 mode encodes bytes rather than characters.

  • Base64 suits binary payloads.
  • Percent-encoding is shorter for small ASCII text.

Worked example

Plain Text Data URL
Create a data URL from a simple text string
Input
											Hello, World!
Output
												data:text/plain;charset=utf-8;base64,SGVsbG8sIFdvcmxkIQ==

When to use this

Inline images, SVG previews, and tiny test fixtures build data URLs.

Edge cases

  • A comma in metadata must be encoded.
  • Standard data URLs are not automatically Base64url.
  • Large data URLs can exceed browser or proxy limits.

References