Compress Photos on iPhone and Android

Why phone photos are large

Modern phone cameras have sensors with 12 to 50 megapixels or more. Even with efficient compression, a single photo is commonly 2 to 8 MB, and a burst, a panorama or a high-resolution mode can be bigger. A few hundred photos fill many gigabytes, and sending them over a mobile connection or by email becomes slow or impossible.

The default settings of the camera favor quality over size, which makes sense for the original, but not for every copy that you share. The practical solution is to keep the originals and send or upload smaller copies.

Camera formats on iPhone

iPhones can save photos in HEIF, usually shown as HEIC files, a format that is typically smaller than JPEG at similar quality. In the camera settings, the Formats option offers High Efficiency, which uses HEIF, and Most Compatible, which saves JPEG. The names and the location of the setting can change between iOS versions.

HEIC is not supported everywhere, so when you attach a photo to a message or upload it to a website, the phone often converts it to JPEG automatically. If a website refuses a HEIC photo, switch to Most Compatible for new pictures, or export the existing photo as a JPEG.

Camera formats on Android

Android phones mostly save JPEG, and many models can also use HEIF or raw formats in special modes. High-resolution modes with 50 or 100 megapixels create very large files, and they are usually not needed for sharing. Look in the camera settings for the resolution and the picture size option, and choose a standard resolution when you do not need the maximum.

Settings differ between manufacturers, so check your own camera app. Lowering the resolution in the camera settings reduces the size of all future photos, but it cannot be undone for photos that were already taken.

Compressing in the browser

You can shrink existing photos without an app. Open this page in your phone's browser, tap Choose images and select the photos from your gallery or camera roll. Set the maximum size to 1920 or 1600 pixels and the quality to about 75. The compressor works through the list, shows the size before and after each photo, and offers each as a download.

The photos are processed on your phone and are never uploaded. On iPhone, the downloaded files go to the Files app and can be saved to Photos from there; on Android they usually go to the Downloads folder. Details depend on the browser and the version.

How many photos at once?

The compressor can handle up to 100 images at once, but a phone has less memory than a computer, and big photos take time to process. If the page seems slow, add the photos in batches of 10 to 20. Very large images with more than about 16.7 million pixels are scaled down to that size, because some browsers, including Safari on iPhone, cannot process larger canvases.

A phone photo of 12 megapixels works without any scaling, so most photos are processed as they are. Photos from 48 or 50-megapixel modes are reduced to fit the limit, which is still a very large picture.

Sharing smaller pictures

Many messaging apps compress photos automatically, and some offer an option to send the original quality. If you want to control the result, compress first, then send. For email, aim for photos of 200 to 500 KB each. For uploading to a form or a website, follow the stated limit.

The share sheet on many phones also lets you choose a smaller size or remove the location from the photo before sending. These options depend on the app and the version; they are worth a look in your settings.

Freeing up storage

Compressing copies does not free space on the phone as long as the originals remain. To really save storage, upload the originals to a backup service or your computer, then delete them from the phone. Smaller compressed copies can stay for sharing.

If you want to keep only one version, think about what you may need later. A printed photo book needs the full resolution, while photos that are only viewed on screens may be fine at 2000 pixels. When in doubt, keep the original.

A last tip is to check the result on the phone itself before you send it: open the compressed copy and zoom in on a face or on text. If it looks good at the size where the recipient will see it, the setting is right, and you can apply it to the rest of the batch with confidence.

Keeping your photos private

Photos on a phone often contain more than you intend: location, the time, and in the background other people or documents. Compressing a copy in the browser removes the metadata, but it does not blur faces or hide a document in the background. Check each picture before you share it, especially pictures of children and pictures taken at home.

If you want the added safety of never uploading a picture, this tool is built for it: all work happens on your phone, and nothing is sent to a server. You can even switch to airplane mode after the page has loaded and it should still work.