UnderByte

Strict upload limits, solved

Make files fit strict upload limits.

No upload. No guessing. Pick the exact cap your portal demands, drop a PDF, photo, signature, or image, and download a file that fits.

Compress a File Free → See Paid Options

First file free. More today for $3.99. Works on your phone.

photo.jpg

4.2 MB → 187 KB

q=84 · target 200 KB · 0.8s

Precise.

Hit the exact limit - 200 KB, 50 KB, whatever your form demands. No overshooting, no blurry results.

Private.

Your files stay on your device. We never see them, upload them, or store them. Close the tab and they are gone.

Affordable.

Your first file is free. Today Pass unlocks more files and batch up to 20 at a time for 24 hours, or choose $19 Lifetime when upload limits keep coming back.

How it works

1. Pick your target.

Choose 200 KB, 50 KB, or any custom limit. Your form knows the number - now your compressor does too.

2. Drop your file.

JPG, PNG, WebP, or PDF. Up to 50 MB. Your browser does the work. We do not see it, and neither does anyone else.

3. Download.

Get your file at the highest possible quality under your target, in two clicks.

What it's for

Online forms with size caps.

Job, school, and account-signup forms with hard upload caps and no patience for files that miss by a little.

Photo and signature uploads.

Profile photos and signature images that have to land under an exact size before a form will accept them.

Job applications.

Resume and document uploads with strict size caps, plus the usual scramble when a PDF export misses by just enough to get rejected.

Scanned documents.

Multi-page scans that come out too large for an upload form that needs a smaller file without sending it to a random website.

Email attachments.

Get a PDF under your provider's cap without rescanning, resaving, and hoping a different export setting works.

Any tight limit.

If the portal demands an exact file size and rejects anything bigger, UnderByte lands you right under the line.

Popular exact-size tools

Compress PDF to 1MB

A common target for resumes, supporting documents, and application uploads.

Questions

Is my file really private?

Yes. The compressor runs entirely inside your browser. Open DevTools, use the Network tab, drop a file on /app, and you will see zero uploads.

Which formats do you support?

JPG, PNG, WebP, and PDF. Output stays JPG, PNG, or PDF.

What's free and what's paid?

Your first file is free. More files today are $3.99. Lifetime is $19: one payment, future upload limits covered, no subscription.

What happens if my target is too small to hit?

We tell you. If quality would collapse or the portal floor is higher than your target, the app warns instead of quietly handing you a broken file.

Why is my portal still rejecting the file?

File size is only one rule. Some portals also care about dimensions, file extension, or exact filenames like photo.jpg.

Does this work on mobile?

Yes. Safari on iOS and Chrome on Android both work. For PDFs above 20 MB, desktop is safer because mobile browsers hit memory limits sooner.

Is the $19 a subscription?

No. The $3.99 Today Pass and $19 Lifetime option are both one-time payments. No renewal. No auto-charge.

What if UnderByte cannot help?

If UnderByte cannot help your file fit, email hello@underbyte.app.

Your files never leave your browser. Drop a file, open the Network tab - zero uploads. That's the whole design. Read how it works.

Desktop app with watch folders and smarter PDF handling is next.

Batch is already available in the browser with a Today Pass or Lifetime. The desktop version will widen file limits, preserve more PDF structure, and add file-system shortcuts.

Email me when it's ready Restore Lifetime

Questions any time: hello@underbyte.app