PDFConvertersOnline.comHow to resize an image
- Choose one or more pictures (JPG, PNG, WebP, HEIC, AVIF and more).
- Pick Size, Percentage or Presets. If the new shape differs from the photo, choose crop, fit or stretch.
- Select the output format, press Resize and download the files.
Three ways to set the new size
- Size: type a width and a height in pixels. With Keep proportions ticked, you only enter one of them and the other follows the picture's own shape, so nothing is squashed. For a batch, each image keeps its own proportions at the width (or height) you typed.
- Percentage: scale everything by the same factor, from 1% to 200%. 50% halves both width and height, which leaves a quarter of the pixels.
- Presets: one click for common targets such as Instagram posts and stories, YouTube thumbnails, Facebook, X and LinkedIn headers, link preview images, Full HD and 4K.
When the shape changes: crop, fit or stretch
Turning a 3:2 camera photo into a 1:1 square or a 16:9 banner means the picture and the frame no longer match. You choose what happens:
| Option | Result | Best for |
|---|---|---|
| Crop to fill | Fills the frame completely; the edges that stick out are cut off. Drag the preview to choose which part stays. | Social posts, banners, thumbnails |
| Fit with background | The whole picture is visible, with bars of a color you pick (or transparent for PNG and WebP). | Product photos, logos, anything that must not be cut |
| Stretch | Forces the picture into the frame, distorting it. | Textures and backgrounds where distortion doesn't matter |
Quality when making pictures smaller or bigger
Shrinking is done in several halving steps with high-quality smoothing, which avoids the jagged, shimmering look you sometimes get from a single big reduction. Enlarging is possible up to 200%, but no tool can invent detail that the original doesn't have; a small picture blown up will look soft. For the sharpest result, always resize from the largest original you have.
Output format and file size
By default each file keeps its format. JPG, PNG and WebP can also be chosen for all files at once, and JPG and WebP get a quality slider. HEIC and AVIF photos are saved as JPG when the format is left on "Same as original". If what you need is a smaller file rather than fewer pixels, Compress Image is the better tool; to cut out a specific area by hand, use Crop Image.
Common sizes worth knowing
Screens and platforms settle on a few sizes again and again: 1920×1080 (Full HD) for wallpapers and slides, 1200×630 for link preview images, 1080 px wide for many social posts, and around 400×400 for profile pictures. All of them are in the preset list. For exact platform sizes with advice on framing, there are dedicated pages for Instagram, YouTube thumbnails, Facebook covers, X headers and LinkedIn banners.
More ways to use this tool
Frequently asked questions
Does resizing reduce file size?
Making a picture smaller in pixels almost always makes the file smaller too. Halving the width and height leaves about a quarter of the pixels.
Can I resize many images to the same width?
Yes. Add them all, choose Size, keep proportions ticked and type the width. Each image gets that width and its own matching height.
Will a transparent PNG stay transparent?
Yes, as long as the output is PNG or WebP. With Fit with background you can also tick Transparent for the empty bars.
Why does my enlarged picture look blurry?
Enlarging spreads the existing pixels over a bigger area. It can't add real detail, so keep enlargement small or start from a bigger original.
Is there a maximum size?
Output up to 20,000 px per side can be typed, but very large images depend on your device's memory. Nothing is uploaded, so there is no server limit.