Browser and computer issues: when ReadyPixl runs slow or weird

Slow performance, browser crashes, Safari memory issues, mobile limitations — and the simple fixes for each.

ReadyPixl runs in your browser. Browser quirks matter more than you'd think. This article covers what happens when your browser or computer is the problem (not ReadyPixl itself).

ReadyPixl runs really slow

Most common cause: big images + big batch + browser memory pressure.

Try these in order:

  1. Close other browser tabs. Each open tab uses memory. ReadyPixl needs that memory for image processing.
  2. Refresh the ReadyPixl tab. Long sessions accumulate memory. A refresh clears it. (Save your pipeline as a preset first if you have one.)
  3. Reduce your batch size. Try 50 images instead of 500. Bigger batches = more memory pressure.
  4. Reduce your source image sizes before loading them. Images larger than ~4000 pixels on a side make every tool slower. Resize to 2000-4000 px first if you don't need the full resolution.
  5. Switch to Chrome or Edge if you're using Firefox or Safari. Both handle big batches better in our testing.

Safari runs ReadyPixl slower than Chrome

This is real. Safari has stricter per-tab memory limits than Chrome and Edge. For batches over ~200 images, Safari noticeably slows down.

Workarounds:

  • Use Chrome or Edge for big batches
  • Stay under 200 images per batch in Safari
  • Close all other Safari tabs while running

We track Safari performance and want to improve it, but for now the recommendation stands.

Firefox is slower than Chrome too

Firefox handles ReadyPixl fine for small to medium batches. For large batches it's noticeably slower than Chrome — usually because of how Firefox handles WebGL and parallel image processing.

If you prefer Firefox for everything else, that's fine — just switch to Chrome for big ReadyPixl batches.

My browser tab crashed

Why: the tab ran out of memory. Big images + big batch + long session adds up.

Recover:

  1. Reopen ReadyPixl
  2. Load your saved preset (if you saved one)
  3. Reload your batch (you'll need to re-pick the images)
  4. Run again

Prevent next time:

  • Save pipelines as presets so you don't lose them on crash
  • Reduce source image sizes
  • Run smaller batches
  • Use Chrome or Edge

Images load but the canvas is blank

Possible causes:

  1. The first image in your batch is corrupt. Click a different thumbnail in the filmstrip. If that one previews fine, remove the corrupt one.
  2. You're zoomed in or out of the page. Reset browser zoom to 100% (Ctrl+0 / Cmd+0).
  3. An ad-blocker or privacy extension is blocking something ReadyPixl needs. Try disabling extensions for readypixl.com. (Privacy extensions sometimes block the WebAssembly that ReadyPixl uses.)

Batch finished but downloads aren't starting

Possible causes:

  1. Browser blocked automatic downloads. Check the address bar for a download blocked notification. Click and allow.
  2. Pop-up blocker interfering. Same fix.
  3. Disk space full. Especially relevant for big batches — a 200-image zip can be 1-3 GB.

"This image is too big to load" error

ReadyPixl blocks images larger than 10000 × 10000 pixels to prevent your browser from crashing.

Fix: resize the image before loading. Use:

  • Mac Preview — open image, Tools → Adjust Size
  • Windows Photos — open image, three-dot menu → Resize
  • Free online resizer — many options, quick fix

Get the image under 10000 pixels on the longer side. Most workflows don't need images bigger than 5000-8000 pixels anyway.

Mac vs Windows differences

ReadyPixl runs the same on both, with two minor differences:

  • Keyboard shortcuts — Mac uses Cmd, Windows uses Ctrl (e.g., Cmd+Z vs Ctrl+Z)
  • File pickers — Mac and Windows have different file picker UIs, but both work the same for ReadyPixl

Neither OS is "better" for ReadyPixl. Use whichever you have.

Mobile (phone / tablet) is too slow

Mobile browsers have stricter memory limits than desktop. ReadyPixl works on mobile, but for any serious bulk work you should use a computer.

See Using ReadyPixl on a phone or tablet for the full mobile rundown.

My computer fan is loud during a big batch

That's normal. Image processing uses a lot of CPU, and your computer ramps up cooling to handle it. Once the batch finishes, the fan calms down.

If your computer is genuinely overheating (slowing down, getting too hot to touch), close other apps and process smaller batches.

ReadyPixl is fine but my internet is slow

Standard ReadyPixl tools run in your browser — no internet needed once the page is loaded. So slow internet shouldn't slow processing.

What slow internet does affect:

  • Initial page load (the first time you open ReadyPixl)
  • Saving presets to your account (sync needs internet)
  • Sign-in / account features

For pure pipeline processing, you can disconnect after the page loads and ReadyPixl still works.

Privacy extensions blocking things

Some privacy extensions (uBlock Origin in aggressive mode, NoScript, Privacy Badger) block the WebAssembly or workers ReadyPixl uses for processing. Symptoms:

  • Images load but never process
  • Tools have no effect on the canvas
  • Errors in the browser console (open with F12) about blocked workers

Fix: add readypixl.com to your privacy extension's allowlist. Or use a different browser without those extensions for ReadyPixl.

When all else fails

  1. Clear your browser cache for readypixl.com (Settings → Privacy → Clear browsing data → just for this site)
  2. Try in an incognito / private window with extensions disabled — if it works there, an extension is the problem
  3. Try a different browser — if it works in Chrome but not Firefox, you've isolated the issue
  4. Reach out via the Feedback link with your browser, OS, and a description of what's happening

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