Image Resizer

What you can do with this resizer

Every place an image ends up has its own idea of the right size. A website banner might need 1920 pixels across, a product listing 1000 x 1000, an email newsletter 600 wide, and a slide only needs as many pixels as a projector can show. Resizing changes the number of pixels in the picture, which is different from compressing it: fewer pixels means a smaller file, faster pages and images that fit the box they are meant for. This tool resizes one image or a batch of up to 20 to the same rule, and lets you choose the format of the result.

Step by step

1. Add JPG, PNG or WebP images by dropping them on the box or tapping it.
2. Choose Pixels to give a width, a height or both, or Percentage to scale every image by the same amount.
3. In pixel mode, decide whether to keep the aspect ratio. Keeping it means the picture is never squashed.
4. Pick the format to save in, or leave it as the original.
5. Each image shows its old and new size in pixels and its new file size. Download them one by one or all together.

How the width, height and ratio options work

With the aspect ratio kept and only a width typed in, the height is worked out from the image's own shape, and the same goes the other way round. If you type both a width and a height, the image is made as large as possible while still fitting inside that box, so one side matches and the other is smaller. This is handy for a batch that mixes portrait and landscape photos: a 1200 x 1200 box makes both kinds 1200 pixels on their longest side. If you choose to ignore the ratio, the image is set to exactly the width and height you typed, stretching it if the shape differs. A blank field then keeps the original value for that side.

Percentage mode multiplies both sides by the same number, so 50 percent halves the width and the height and leaves a quarter of the pixels. Values above 100 make the image bigger.

A worked example

A typical 12 megapixel phone photo is 4032 x 3024 pixels. A width of 1200 with the ratio kept gives 1200 x 900. A 1080 x 1080 box gives 1080 x 810, because the photo is wider than it is tall. 25 percent gives 1008 x 756. Ignoring the ratio and typing 1080 x 1080 gives a square image in which everything looks a little narrower than in real life. Going from 4032 to 1200 pixels across leaves about 9 percent of the original pixels, so the file usually shrinks from several MB to a few hundred KB.

Quality, formats and limits

Large reductions are done in halves, one step at a time, which keeps fine lines sharper than a single big jump. JPG and WebP are saved at 90 percent quality. PNG is lossless and keeps transparency but makes much bigger files for photos; when a transparent PNG is saved as JPG, the transparent parts become white. Making an image larger cannot invent detail that was not captured, so an enlarged photo looks soft. Each side is limited to 10,000 pixels, because browsers, phones in particular, cannot draw bigger images reliably. Camera details such as location are not copied into the resized files.

Your images stay with you

Resizing is done by your browser's own image tools on your device. No image is uploaded to Ur Next Door or anywhere else. For a size limit in KB rather than in pixels, the Image Compressor is the better fit.