App Store Connect and the Play Console both accept enormous image files without complaint — right up until slow uploads, a bloated app bundle, or a rejected listing tell you otherwise. Compressing images before submission isn't optional busywork; it's the difference between a snappy listing and one that quietly hurts your conversion rate. Here's how to do it without the screenshots looking noticeably worse.

Which images actually need compressing

Three categories, each with a different target:

The setting that matters most: quality, not just format

Switching to a modern format helps, but the single biggest lever is the quality setting on export. Most screenshots and photos hold up fine at 70-85% JPEG or WebP quality — the difference from 100% is invisible at normal viewing size, but the file size difference is often 60-80%.

FILE SIZE vs QUALITY SETTING 100% 4.1 MB 85% 1.3 MB 70% 640 KB 40% 210 KB visible quality loss starts here
A realistic curve: quality below ~60-70% is where compression artifacts start becoming visible.

Which format to export as

Use caseBest formatWhy
App Store / Play Store screenshotsPNG or high-quality JPEGBoth stores accept PNG and JPEG; PNG is required for some transparent overlays.
In-app photosWebP or AVIF20-50% smaller than JPEG at equal visual quality, supported on modern Android/iOS.
In-app icons and flat-color graphicsPNGLossless, and flat colors compress well without needing a photo-oriented format.

Step by step with a batch tool

  1. Open the image compressor and drop in every screenshot or asset you need to prepare — it accepts a full batch at once, not one file at a time.
  2. Pick a target format: JPEG for universal compatibility, WebP or AVIF for smaller files on modern platforms.
  3. Adjust the quality slider while watching the live before/after preview — stop as soon as you can no longer tell the difference at normal zoom.
  4. Compress the whole batch and download it as a single ZIP.

If you also need to resize (many screenshot tools export at a higher resolution than the store requires), the compressor's resize option handles that in the same pass — no need for a separate step.

Compress your screenshots and assets now

Batch JPEG, PNG, WebP, and AVIF compression with a live before/after preview — free.

Open the Image Compressor →

Don't forget the screenshots themselves

If you haven't generated your store screenshots yet, doing it with the right tool avoids the compression problem at the source — the screenshot generator exports directly at the exact pixel sizes App Store Connect and the Play Console require, so there's no oversized export to compress down in the first place.

FAQ

What's the maximum screenshot file size for the App Store?

Apple accepts screenshots up to 500 MB each, but that's not a target to hit — under 1-2 MB per screenshot is plenty for full quality and uploads far faster.

Does compressing images affect app review?

No — reviewers judge screenshots on how they represent the app, not file size. Compression only affects upload speed and, for in-app assets, your final download size.

Should I compress images before or after resizing?

Resize first, then compress — compressing an oversized image and then shrinking it wastes the compression pass, since resizing changes the pixel data again.

Related guides

WebP vs PNG for Mobile Apps How to Reduce App Size (Android & iOS) Generate App Store & Play Store screenshots at the right size