Capabilities

Drag and drop
Local file intake
Download result

Try it

Supported formats

Input: application/pdf, text
Output: text, application/pdf
Files: Local file intake and drag/drop

Privacy

Runs entirely in your browser. Your input is never uploaded, stored, or sent to a third party.

Processing: In your browser
Privacy level: Browser only

Converted bytes to Base64: 53 byte(s); the result starts with %PDF-.

How it works

Decode the source bytes with the dependency-free codec.
Re-encode the result in the standard alphabet.
Check the decoded bytes for the %PDF- header and report the exact byte length.

No PDF object parsing is performed; the bytes are copied unchanged.

Methodology

Encode: read the local PDF bytes and emit Base64 in the standard or URL-safe alphabet, optionally with a data-URL prefix.
Decode: decode the Base64 with a strict, dependency-free RFC 4648 decoder; malformed input is a named finding.
Check the decoded bytes for the %PDF- magic and report the exact byte length, never guessing the file type.

Usage

Choose whether to encode a PDF or decode Base64.
Pick the alphabet and whether to include a data-URL prefix.
Run the conversion to copy or download the result.

Examples

These are examples, not current values: they use fixed inputs, while the interactive tool computes live results in your browser.

Encode a minimal PDF to Base64

{
  "mode": "encode",
  "data": "JVBERi0xLjQKJcOkw7zDtsOfCjEgMCBvYmoKPDwvVHlwZSAvQ2F0YWxvZz4+CmVuZG9iago=",
  "alphabet": "standard",
  "dataUrlPrefix": false
}

Decode Base64 to bytes

{
  "mode": "decode",
  "data": "JVBERi0xLjQKJcOkw7zDtsOfCjEgMCBvYmoKPDwvVHlwZSAvQ2F0YWxvZz4+CmVuZG9iago=",
  "alphabet": "standard",
  "dataUrlPrefix": false
}

Limitations

A faithful, local conversion

Encoding and decoding use a strict RFC 4648 codec. In encode mode the bytes are copied unchanged; in decode mode a malformed string is reported by name instead of silently dropping characters.

The tool checks the decoded bytes for the %PDF- magic so a non-PDF payload is labelled honestly.

Frequently asked questions

Is my PDF uploaded?: No. The bytes are read and converted locally in your browser; nothing is uploaded, stored or logged.
Which alphabets are supported?: Standard Base64 and its URL-safe variant (RFC 4648), with an optional `data:application/pdf;base64,` prefix.

Sources

Send feedback

Tell us if this tool helped, report a problem, or suggest a tool. Only the message you type is sent — never the input you used in the tool.

Was this tool useful?

Prefer to write to us directly? See the contact page.