How it works

How ByteRivet processes your files

Generated test files stay on your device. Browser tools process locally; Office conversions upload documents to a server. Page assets and analytics can make network requests.

Three steps.

No account, no upload screen, no processing queue — the whole thing runs between when you click and when the file lands in your downloads folder.

1. Pick a format

Choose from 19 real container formats — PDF, PNG, ZIP, DOCX, XLSX, CSV, MP3 and more.

2. Set the exact size

Type a size or drag the slider. The generator works out how much padding a valid file at that size needs.

3. Generate and download

JavaScript assembles the file in your browser. The generated file is not uploaded; page assets and analytics still make network requests.

Three processing models, not one.

ByteRivet is three product families, and they don't all work the same way. Here's exactly what happens to your file in each one — no blanket claims, just what's actually true for the tool you're using.

Test File Generator

Generates a structurally valid file at an exact byte size — for testing upload forms, size limits and automated pipelines.

  • Processing location: Your browser
  • Technology: JavaScript, in a Web Worker
  • Upload status: Never uploaded
  • Retention: Nothing to retain — the file never leaves your device

Known limitations

  • Limited by your browser's available memory, not by the tool itself
  • Very large files (500 MB+) may trigger a browser memory warning

Browser-based PDF & Image Tools

Merge, Split, Organize and Watermark PDF; Compress, Convert, Crop, Resize and Rotate Image; Images to PDF, PDF to Images and Image to Text (OCR) — twelve tools that all run locally.

  • Processing location: Your browser
  • Technology: pdf-lib and the Canvas API; Tesseract.js for OCR
  • Upload status: Never uploaded
  • Retention: Nothing to retain — the file never leaves your device

Known limitations

  • Password-protected or encrypted PDFs aren't supported by the PDF tools
  • OCR reads English text only, and only the first page of a PDF

Server-based Office Conversions

Office to PDF and PDF to Office — the two tools that need a real document engine, which only a server can run.

  • Processing location: Our server
  • Technology: LibreOffice, over HTTPS
  • Upload status: Uploaded for the duration of the conversion
  • Retention: Source deletion is attempted after processing. Results become eligible for queue cleanup after 15 minutes and are also deleted after their first download. See Security for job metadata retention.

Known limitations

  • PDF to Excel isn't offered — a spreadsheet can't be reliably rebuilt from a PDF's layout
  • Complex layouts, unusual fonts or advanced formatting may look slightly different from the original