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Reduce image resolution

Got phone photos with a huge resolution that take up far more space than they need? Reduce them to 4K, 2K or Full HD here, a whole series at once, without changing the aspect ratio.

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Modern phones shoot photos with a lot of megapixels, but a TV, a monitor or a website needs far fewer. Smaller copies are handy for sharing with family, for slides or for a website, and they take up less space in the cloud. Choose your photos, keep 4K or pick a smaller size, and download them. Below you'll find how many pixels 4K, 2K and 1080p are, what's enough for a print and how to save space on the phone itself.

How to reduce image resolution

  1. 1

    Add your photos

    Drag photos from your phone or camera onto the page. The tool accepts JPG, PNG, WebP and HEIC from iPhone, a whole series at once.

  2. 2

    Keep 4K or choose less

    The longest side is set to 4K (3840 px) by default. For a website or slides, choose 2K (2560 px) or Full HD (1920 px).

  3. 3

    Add a size limit if needed

    If a service also limits the file size, pick a target in KB or MB. Otherwise leave it at No limit.

  4. 4

    Download your photos

    Each photo shows its new file size. Several photos come in one ZIP with -compressed added to the names.

Smaller photos straight from the phone

On supported models, the iPhone's main camera shoots 24 MP by default. In Settings > Camera > Formats > Photo Mode you can switch to 12 MP. The Galaxy S23 Ultra with its 200 MP sensor shoots in 12 MP mode by default.

How many pixels are 4K, 2K and 1080p

A 4K TV or monitor has 3840 × 2160 px, so a 16:9 landscape photo at 4K fills the whole screen. A photo with a different aspect ratio, or a portrait one, gets borders around it. For a website, slides or viewing on a phone, Full HD, also called 1080p, with a 1920 px long side is usually enough. 2K at 2560 px is a middle ground for bigger monitors.

This page caps the longest side and works out the other side from the aspect ratio, so nothing gets stretched. A 4:3 photo reduced to Full HD comes out at 1920 × 1440 px. If you need exactly 1920 × 1080 px from such a photo, use Resize image with Width and height and Fill and crop.

What resolution is enough for printing

A 4 × 6 inch print at 300 DPI needs 1200 × 1800 px, and a US Letter page of 8.5 × 11 inches needs 2550 × 3300 px. A 4:3 photo at 4K has 3840 × 2880 px, enough for both with room to spare. For large prints, such as a canvas for the wall, keep the original.

Free up space on your phone and in the cloud

Smaller copies suit an archive, sharing with family or viewing on screen. Keep the originals in at least one place, though, because removed pixels can't be brought back.

If phone storage is your main concern, check your cloud settings first. Google Photos offers Original quality or Storage saver when backing up, and in some countries also Express. On an iPhone, Optimize iPhone Storage keeps smaller versions on the phone while the full-size originals stay in iCloud.

Privacy

Images are processed in your browser and never uploaded to a server. Some tools remember your settings on this device, and the files you download stay on it.

FAQ

How do I lower the resolution of a photo?
Add the photo, choose 4K, 2K or Full HD under Longest side and click Reduce resolution. The longer side shrinks to that size and the shorter one follows the aspect ratio. Photos that are already smaller keep their dimensions.

How many pixels is a 4K photo?
The longest side has 3840 px and the shorter one follows from the aspect ratio. A 4:3 photo comes out at 3840 × 2880 px, a 16:9 photo at exactly 3840 × 2160 px, like a 4K TV. For a portrait photo, the height is 3840 px.

How do I resize a photo to 1080p?
Choose Full HD (1920 px) under Longest side. A 16:9 photo becomes 1920 × 1080 px and a 4:3 photo 1920 × 1440 px. For exactly 1920 × 1080 px whatever the shape, use Resize image with Fill and crop.

Does reducing resolution reduce file size?
For high-resolution photos, yes: fewer pixels mean a smaller file. How much smaller depends on the photo. If you need the file under a certain limit, choose a target size in KB or MB as well as the dimensions.

Is DPI the same as resolution?
No. Resolution here means the number of pixels. DPI is only a note in the file saying how densely to print them, and changing it doesn't add or remove a single pixel. To make a photo smaller, change its pixel dimensions, as this page does.

Does a photo lose quality when reduced to 4K?
It loses detail you wouldn't see on a 4K screen anyway. Viewed on a monitor, a TV or a phone, you won't notice the difference. When you crop or print large, the missing pixels do show, so keep your originals.

Can I make a picture 4K?
Not here. The tool never enlarges photos, because enlarging adds pixels but no detail, so a photo smaller than 4K keeps its original size. Programs that promise to upscale to 4K have to guess the missing detail. If you have a higher-resolution original, use that.

Can I reduce the resolution of a whole series at once?
Yes. Add the whole series, all the photos from a trip for example. Each one shrinks to the chosen size and you download them in one ZIP. Landscape and portrait photos are both reduced by their longer side.

Do my photos stay on my device?
Yes. Photos are resized right in your browser and never sent anywhere, and the tool is free with no sign-up. You can shrink a whole family archive without uploading it to someone else's server.

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