How to Resize an Image (Online or Offline)

If you're a Windows 11 or Windows 10 user, you'll already be familiar with the Photos app. What you might not know is that you can use it to perform some basic editing tasks, including as a picture resizer. Here's how:

1. Open your image, press the three dots in the toolbar, then click “Resize”

   

2. Option 1: Choose between one of the presets 

   These are generally pretty accurate. The emails and messages option is particularly great if you run into a file size limitation when trying to send an image in a messaging app.

   

3. Option 2: Press “Define custom dimensions”

   

4. Enter your width, height, and quality settings and press “Save resized copy”

   It's a good idea to tick “Maintain aspect ratio”, as this will stop your image from being “stretched” to be wider or taller than the original image.

   You can also adjust the “Quality” slider, which will determine how much the image is compressed. The important thing to keep an eye on while doing so is the size below the “Resize image” heading. You can try to find a good combination between file size, resolution, and quality.

   

5. Choose your folder and press “Save”

   Photos will save the image copy to the folder of your choice with its new dimensions and quality settings.

   

Resizing an image in Microsoft Paint used to destroy its quality, but these days it's not bad. Conveniently, you can also resize as a percentage, which is more intuitive than manually working out pixel numbers:

1. Press “File > Open” in Microsoft Paint

   

2. Find the image you want to resize, click it, and press “Open”

   

3. Press the image resize icon in your ribbon

   This should look like a square with a picture in the bottom-left corner and a diagonal arrow.

   

4. Enter the percentage you want your final image to be and press “OK”

   For example, if you were to set your percentage to 150, it would be 1.5x the size of your original image. 50% would half the size of your image.

   

5. Press “File > Save as > File format”

   You can choose the file type that best suits your purpose. JPEG is a lossy file format, meaning you'll lose some quality if you're coming from a different format. PNG uses lossless compression, so you'll get a better quality but a higher file size.

   We do not recommend that you use BMP for resizing at all. Resizing a BMP is akin to resizing the individual pixels, which will mean a fuzzy or jagged result.

   We only recommend GIF if you have an image without a lot of color variation. As GIF has a limited color palette, you may see blockyness otherwise.

   

6. Name your file and press “Save”

   

If you don't have suitable software on your PC or are on a mobile device, you can use a free image resizer website to make your image smaller or bigger. There are a ton of options out there and using an image resizer online is very easy:

1. Picresize.com

   PicResize is very easy to use. All you need to do is drag and drop your image and select from a variety of resize presets. You can even apply effects such as frames and oil painting effects.

   The only downside is that you can only use picresize to make an image smaller unless you pay for its pro version. 

   

2. Resizeimage.net

   ResizeImage is a bit more advanced tool, though it does have a “simple” mode if you don't need the additional functionality. You can crop your image using the tools pictured below, which is always nice, as well as rotate.

   

3. Adjusting your image size

   Regardless of the options you choose, you'll be presented with a “Resize your image” slider to easily adjust the percentage it's scaled. Much like picresize, you can't go above 100% when resizing. You can, however, adjust the amount of compression in your image.

   

If you already have image editing software installed, it can make sense to use that rather than Windows in-built tools. The process to change a photo's similar in all of these apps, but we'll be using paint.net as an example.

1. Open your image editing software and choose “File > Open…”

   

2. Select your image and press “Open”

   

3. In the toolbar, press “Image > Resize”

   

4. Choose your new dimensions (via pixels or percentage) and press OK

   

5. Click “File > Save As…” in the toolbar

   

6. Name your resized image and press “Save”