How to compress photos on iPhone and Android

SlimPic guide · Updated September 29, 2026

High-resolution phone photos can exceed email and upload limits. SlimPic processes supported images in your browser without a separate compression app, an account, or an image upload to a server.

Compress a photo on your phone

1. Open SlimPic and tap Choose photos.
2. Select JPG, PNG, or WebP files from the file picker or photo library available on your device.
3. Choose the maximum size, such as 500KB or 1MB.
4. Tap Compress photos and keep the tab open while it processes.
5. Check the dimensions and format, then download the result.

If an iPhone photo will not open

The original may be HEIC or HEIF, which SlimPic currently does not accept. Check your device’s export or share options for a way to save a JPEG copy. Available controls vary by app and operating system. Renaming a HEIC file to JPG is not conversion.

Where are downloaded photos saved?

Your browser may save files to a Downloads folder or Files app rather than directly into your photo library. Open the browser’s download list to locate the file. If you download several images as a ZIP, extract it first. You can then use your device’s own controls to save individual images to the photo library.

Why very large images can be slow

A 10MB file needs more memory when decoded. A 48-megapixel image alone can occupy about 192MB as raw RGBA pixels, before additional decoder memory. SlimPic processes images one at a time and limits processing resolution, but cannot remove device memory limits.

If processing stops, try fewer photos, close unnecessary tabs, or use a smaller source. Switching apps or locking the screen may suspend browser processing. Your original files remain unchanged.

Check orientation and details

Phone JPEGs may use EXIF orientation. SlimPic accounts for image orientation during decoding; use the comparison before saving. Re-encoding does not preserve EXIF or GPS metadata. An unchanged original can still contain its original metadata.