How to Reduce Image File Size Without Losing Quality

Why file size matters

Many websites and government forms limit uploads to a few hundred kilobytes. Email services cap attachments. Heavy images also slow a website down, and slow pages lose visitors. A modern phone can easily produce a 5 MB photo, so shrinking pictures is something almost everyone needs to do.

Step 1: Resize the dimensions first

This is the biggest lever. A photo that is 4000 pixels wide, shown in a space 1200 pixels wide, wastes most of its pixels. Halving both width and height removes about three quarters of the pixels. Use the resize tool to set a width that fits where the picture will be used.

Step 2: Pick the right format

Photos belong in JPG or WebP. Screenshots and graphics with text look better as PNG, but they are bigger. If you have a photo saved as PNG, converting it to JPG can cut the size dramatically. Our format guide explains the choice.

Step 3: Lower the quality a little

For JPG and WebP, a quality setting of roughly 70 to 85 percent usually looks nearly identical to the original at a much smaller size. Compare the before and after previews and stop when you start to notice a difference. The compress tool lets you pick a quality level.

Step 4: Aim for a target size

When a form says “under 100 KB”, type that number as the target size in the compress tool, and let it find the quality setting for you. If it cannot reach the target, resize the picture smaller first.

Step 5: Remove hidden data

Photos carry camera and location information. Removing it saves a little space and protects your privacy. See our guide to Exif data and the Exif remover.

Rules of thumb for sizes

• Pictures inside a blog post or product page: often 100 to 300 KB.
• Small thumbnails and icons: usually under 50 KB.
• Form uploads: whatever the form requires, and always check the limit.

These are guidelines, not rules. A detailed photograph needs more bytes than a simple graphic.

A worked example

Say you have a 4000 by 3000 pixel phone photo of 5 MB, and a job portal wants it under 200 KB. Resize it to about 1200 pixels wide. That alone removes roughly nine tenths of the pixels and often brings the file down to 300 to 500 KB. A quality of around 75 percent then takes it under 200 KB, and the picture still looks fine on a screen. Doing the steps in that order gives a better result than compressing the huge original hard.

Mistakes to avoid

• Compressing a picture that was already compressed many times.
• Enlarging a small picture. It gets bigger in pixels but not sharper.
• Compressing screenshots of text into blurry JPGs.
• Deleting your original. Always keep an untouched copy.

Frequently asked questions