Convert ASCII to Data URI

Convert ASCII to Data URI turns a standard ASCII string into a self-contained data URI. A data URI stores a small payload directly inside a URI using a media type and either percent-encoding or Base64. This is useful for inline text, small examples, browser demonstrations, generated snippets, and situations where a tiny piece of data needs a URI-shaped representation without a separate file URL.

The tool offers two practical output forms. Plain text mode uses a text/plain media type and percent-encodes characters that are not safe or convenient to place literally in a URI. Base64 mode encodes the ASCII bytes first and places the resulting Base64 string after the media type. Both formats represent the same source characters, but they are useful in different contexts. Plain mode is easier to read; Base64 mode is often easier to copy when the payload contains many special characters.

Input is deliberately restricted to standard ASCII. That keeps the byte interpretation deterministic and makes the relationship between the source text and the generated URI easy to explain. If your real payload contains Unicode, the correct workflow is to encode the text as UTF-8 bytes and then construct a UTF-8-aware data URI rather than silently treating Unicode as ASCII.

Load the sample and compare the two output modes. Then test a phrase containing spaces, punctuation, ampersands, and percent signs. The statistics show how the URI expands relative to the original text. Because the output stays in a text area, you can inspect the complete prefix, media type, encoding marker, and payload before copying or downloading it.

Data URIs are convenient, but they are not automatically appropriate everywhere. They can make HTML, CSS, configuration, or documentation less readable when the payload becomes large. Treat this tool as a small-data utility rather than a replacement for normal files or URLs. It is especially useful when the source is short and you deliberately want the data embedded into a URI.

The browser-side workflow is the same as the other tools: Load Sample, Clear, Convert, Copy, and Download. Download saves the generated URI as text rather than trying to interpret it as a live resource. This keeps the tool predictable and makes it suitable for generating test cases or documentation examples.

A good verification method is to paste the resulting URI into the Data URI to ASCII tool. The decoded result should match the original string character for character. If it does not, inspect whether the data URI contains an unexpected prefix, a missing comma, or a payload that was already encoded before conversion.

Finally, remember that a data URI is a representation, not a permission boundary. It can contain text or other data without contacting a separate server, but whether a browser or application should load that URI depends on the surrounding context and policy. Use the generated value where data URIs are actually supported and keep the embedded payload appropriately small.

• Builds a text/plain data URI from ASCII.
• Offers percent-encoded and Base64 payload modes.
• Validates ASCII input.
• Shows the resulting URI length.
• Provides sample and clear controls.
• Supports Copy and Download.
• Keeps the generated URI as plain text.
• Runs entirely in the browser.
• Pairs with the reverse Data URI decoder.
• Makes the media type and encoding marker visible.

1. Enter ASCII text.
2. Choose Plain text or Base64 mode.
3. Click Convert.
4. Inspect the complete data URI.
5. Copy or download it.
6. Decode it with the reverse tool to verify the round trip.

Plain text. Hello → data:text/plain;charset=us-ascii,...

Base64. Hello → data:text/plain;base64,SGVsbG8=

Spaces. A B produces an encoded URI-safe representation.

Punctuation. A&B is encoded so the ampersand remains payload data.

Verification. Generate a URI and decode it with the reverse tool.

• Creates small self-contained URI values.
• Two encoding modes cover common workflows.
• ASCII validation keeps bytes predictable.
• Useful for snippets and test fixtures.
• Local processing is private.
• Copy/download make reuse easy.
• Round-trip verification is simple.