Image Resizer

What is an image resizer?

An image resizer changes the dimensions of a picture, which means its width and height in pixels. You might need to make a photo smaller so that it fits a form, a web page or an email, or set an exact size for a social media post, a banner or a profile picture.

This tool works inside your browser. Your images are never uploaded to a server, so personal photos and work files stay on your device.

How image resizing works

A digital picture is a grid of tiny colored squares called pixels. A photo that is 4000 pixels wide and 3000 pixels tall has twelve million of them. When you resize the picture, the tool builds a new grid with a different number of pixels and calculates the color of each new pixel from the old ones.

Making a picture smaller keeps it sharp, because the tool only has to combine pixels. Making it bigger is harder, because the tool has to invent pixels that were never there. This is why an enlarged picture can look soft or blurry, and why it is always better to start from the biggest original that you have.

Three ways to resize an image

• By size: Enter a width, a height, or both in pixels. With Keep aspect ratio turned on, you can enter one side and the other is calculated for you, so the picture is not stretched.
• By percentage: Scale the image up or down by a percentage. For example, 50 percent makes it half as wide and half as tall.
• Social presets: Pick a ready-made size for Instagram, YouTube, Facebook, X, LinkedIn, Pinterest or Open Graph. The image is scaled and cropped to fit the exact size.

Step-by-step: resizing your images

• Step 1: Add your images: Drag your pictures into the box or click Choose images. You can add up to 20 images at a time, up to 25 MB each.
• Step 2: Pick a method: Choose By size, By percentage or Social presets, depending on what you need.
• Step 3: Set the size: Enter the numbers, move the slider or choose a preset. The result updates automatically, so you can see the new size before you save.
• Step 4: Choose the output: Optionally pick the output format and the quality. WebP and JPG give smaller files than PNG.
• Step 5: Download: Download each image, or click Download all to save everything at once.

Why image size matters for SEO and speed

Search engines and visitors both prefer fast pages. If you upload a photo that is 4000 pixels wide and show it at 800 pixels, the browser still has to download the full file, which wastes time and data. Slow pages lose visitors, and loading speed is part of the page experience that Google looks at.

A good habit is to resize images to the size they are actually shown at before you upload them, and then compress them. Link previews matter too. When someone shares your page, platforms such as Facebook, LinkedIn and X use your Open Graph image, and a picture of the right size looks sharp and is not cropped in the wrong place.

Common image sizes

• Instagram post: 1080 x 1080 pixels (square). Portrait posts use 1080 x 1350, and stories use 1080 x 1920.
• YouTube thumbnail: 1280 x 720 pixels.
• Open Graph (link preview): 1200 x 630 pixels.
• Facebook cover: 820 x 312 pixels.
• X (Twitter) header: 1500 x 500 pixels.
• LinkedIn banner: 1584 x 396 pixels.

Resizing vs compressing

Resizing changes the dimensions of an image, while compressing reduces its file size without changing the dimensions. For web use, the best result usually comes from doing both: resize first to the size you need, then compress to remove extra weight.

Keep in mind that platforms update their recommended sizes from time to time, so check the platform if you need an exact size for an important post.

Tips for the best result

• Keep the aspect ratio: Turning it off stretches the picture, so faces and logos look wrong. Leave it on unless you really need a different shape.
• Start from the original: Resize from your biggest original instead of an already resized copy, because every resize loses a little detail.
• Avoid enlarging: Making a picture much bigger than its original makes it look soft. If you need a large image, use a larger original.
• Check the crop on presets: Social presets crop the picture to fit the exact size, so keep the important part of the picture near the center.
• Keep your originals: Resizing creates new files. Keep the originals in case you need a different size later.

Common problems and fixes

• My enlarged image looks blurry: The tool had to invent pixels. Use a bigger original, or keep the picture at its real size.
• The picture looks stretched: Keep aspect ratio was off, or both width and height were set to a different shape. Turn it on and enter only one side.
• The file is still large: Resizing lowers the pixel count, but a big file can stay big. Lower the quality, choose WebP or JPG, or use the Image Compressor.
• The preset cut off part of my photo: Presets fit the picture to an exact shape by cropping. Use By size instead if you want to keep the whole picture.

Other image tasks you may need

• Make files smaller: Use the Image Compressor to reduce the file size after resizing.
• Remove a background: Use the Remove Background tool to cut out a subject and save a transparent PNG.
• Pictures into a PDF: Use the JPG to PDF tool to put your resized images into one document.

Resize your images now

Add your pictures in the box above, choose a method and download the new sizes in seconds. It is free, adds no watermark and needs no signup.