Heavy images are one of the biggest enemies of website and online store performance. A page that's slow to load loses visitors — and sales. Compressing images is the simplest, highest-impact optimization for load time, and it can be done for free in seconds.
What is image compression?
Image compression is the process of reducing a file's size without changing (or barely changing) its visual quality. There are two types:
- Lossless: the file gets smaller without changing a single pixel. Works best with PNG and simple images. The size reduction is smaller.
- Lossy: discards information imperceptible to the human eye to reduce the size much more. Works best with photos (JPG and WebP). The reduction can reach 80% with no perceptible visual difference.
What quality level should you use?
| Use case | Recommended quality | Typical reduction |
|---|---|---|
| Websites and blogs | 70–80% | 60–80% |
| E-commerce (product) | 80–85% | 50–70% |
| Social media | 75–85% | 50–65% |
| Email marketing | 70–80% | 60–75% |
| Digital printing | 95–100% | 10–20% |
💡 Rule of thumb: start with 80% quality. If the visual difference isn't noticeable, try 70%. For product photos on marketplaces, 80% is the sweet spot between quality and file size.
How to compress images for free
The ImageTools image compressor lets you adjust quality in real time and see a side-by-side comparison before downloading:
- Open the image compressor
- Drag your image or click to select it
- Adjust the quality slider (default: 80%)
- Compare the original with the compressed version and see how much you saved
- Choose the output format (JPG, PNG or WebP)
- Download the compressed image
To compress several images at once, select multiple files. The compressor processes them in batch and generates a ZIP with all the compressed images.
Which format should you choose?
- JPG: best for photos. Smaller size with good visual quality.
- WebP: up to 30% smaller than JPG at equivalent quality. Supported by all modern browsers. Ideal for websites and online stores.
- PNG: use only when you need transparency. PNGs of photos are much larger than JPG.
Compress your images now
See the savings in real time before downloading. Batch support with ZIP download.
Compress my imagesWhy does compressing images improve your site's SEO?
Google has used load speed as a ranking factor since 2010, and image weight is one of the biggest culprits behind slow pages. Core Web Vitals — Google's set of performance metrics — penalizes sites with a high LCP (Largest Contentful Paint), which is often caused by heavy images.
Compressing a site's images can cut load time in half with no change to the design or content.