How to Resize an Image Without Losing Quality

Resizing is not the same as compressing

Resizing changes the pixel dimensions of an image — a 4000 × 3000 photo becomes 1200 × 900, for example. Compressing keeps the dimensions but stores the same pixels using fewer bytes.

The two work well together. Resize first so the image matches the space it will actually occupy, then compress the smaller result if you need to squeeze the file size further.

Pixels or percentage: which should you use?

• Use pixels when a platform gives you an exact requirement, such as a 1200 × 630 social preview.
• Use percentage when you just want everything smaller — 50% is a fast, safe default for phone photos.
• Keep the aspect ratio locked unless you deliberately want a stretched or squashed result.
• Check the resulting dimensions before you download; percentages round to the nearest pixel.

Step by step

Open the Image Resizer and drag your JPG, PNG or WebP file onto the drop zone. The original dimensions and file size appear immediately.

Choose By pixels and type a new width — with the lock enabled the height follows automatically — or switch to By percentage and drag the slider.

Pick an output format, press Resize, and compare the before and after panels. When you are happy, download the file.

Why upscaling rarely works

Enlarging an image cannot invent detail that was never captured. The browser interpolates between existing pixels, which softens edges and can make text look blurry.

If you need a larger version, always go back to the original file at full resolution rather than upscaling an already reduced copy.

Common mistakes to avoid

• Unlocking the aspect ratio by accident, producing distorted faces and logos.
• Resizing the same file repeatedly — each JPG save adds a little more compression damage.
• Choosing PNG for photographs, which produces needlessly large files.
• Forgetting that retina screens often want images at roughly twice their displayed size.