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Guide File Size Limits PDF

How to Reduce a PDF to Under 100 KB — The Simple Way to Beat Upload Limits

Government portals, legal sites, and old systems often enforce tiny file limits (like 100 KB). Here’s a fast, practical method to meet those caps without wrecking your layout: Split by Size — plus compression tips when you need them.

Reduce PDF to under 100 KB

Updated May 20, 2025 • 8–10 min read

Overview: Why 100 KB Still Matters

Sometimes a form won’t let you submit because your PDF is “too large.” If you’re uploading to a government or legal portal, or sending via email with strict gateways, you’ve probably seen limits such as 100 KB. When compression alone won’t cut it — or when you only need part of a document — the fastest fix is Split by Size.

Key takeaways:
  • Use Split by Size to automatically create multiple PDFs each under your chosen limit (e.g., 100 KB).
  • Perfect for strict upload portals where compression still isn’t small enough.
  • No guesswork — you set the size, the tool handles the rest.
  • Quality is preserved because you’re dividing pages, not over-compressing images.

Step-by-Step: Get a PDF Under 100 KB with Split by Size

  1. Open the Split PDF tool.
  2. Choose Split by Size (enter your limit, e.g., 100 KB).
  3. Upload your PDF (drag & drop supported).
  4. Click Split PDF and wait a few seconds.
  5. Download the resulting files — each one will be under the target size.

When to Use Split by Size Instead of Compression

Why Portals Enforce Tiny Limits

Many government and legal sites still run on older infrastructure designed for low bandwidth. Their upload handlers often cap files at sizes such as 100–300 KB to ensure compatibility and quick processing. You’ll see this on visa portals, identity submissions, e-filing systems, or legacy email gateways.

What Exactly Is “Split by Size”?

Split by Size takes your PDF and creates multiple smaller PDFs that each respect the maximum you provide (e.g., 100 KB). It doesn’t degrade content. Instead, it reorganizes the document into several parts that all pass the upload requirement.

Need Guaranteed Under 100 KB?

Split by Size gives predictable results with no quality surprises.

Use Split PDF Now

Compression Still Helps — Here’s When to Use It

Compression is great when you must keep a single file, or when your document is only slightly above the limit. Try:

Pro Workflow: Combine Compression + Split by Size

  1. First, run Compress PDF to get a reasonable baseline.
  2. Then, run Split by Size to guarantee every output file is under 100 KB.

This two-step workflow minimizes how many parts you end up with while ensuring each part meets the limit.

Important Things to Check

  • Very short PDFs: If your file is 1–2 pages and still over 100 KB, compression is often better than splitting.
  • Image-heavy documents: Try compression first; splitting may still produce segments above 100 KB if a single page has a huge image.
  • Verify content after splitting: Ensure all required pages ended up in the outputs you plan to upload.
  • File naming: Name outputs clearly (e.g., application_part1.pdf, application_part2.pdf).

Use Cases Where <100 KB Is Common

Quality & Security Considerations

FAQ

How do I guarantee a PDF is under 100 KB?

Use Split by Size. Set the limit (100 KB) and the tool outputs multiple files that each stay below the cap. If you need a single file, compress first and export at lower resolution.

Will splitting harm quality?

No. Splitting divides pages into separate PDFs without changing how they look. Compression changes encoding; splitting does not.

What if one page alone exceeds 100 KB?

Compress that page (e.g., reduce image DPI or use OCR), then split again. Image-only scans are the usual culprit.

Can I email multiple split files?

Yes. Most portals accept multi-file uploads. If only one file is allowed, compress more aggressively or combine text-only pages.

Finish Faster: Pick the Right Tool

Compression is perfect for a single file. Split by Size guarantees strict caps like 100 KB.

Split by Size Compress PDF

Conclusion

Strict upload limits don’t have to slow you down. If compression isn’t enough — or you only need to submit part of a document — Split by Size is the most reliable way to meet a 100 KB cap while preserving quality and layout. Use compression first when you need a single file, then split to guarantee the final size.

Written by the PDF Convert Easy Editorial Team

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