An unoptimized 12-megapixel photo can easily be 5–8 MB. That is fine for your camera roll, but it is a problem for websites, email, and social media. The goal is to reduce file size to something reasonable without making the image look noticeably worse. Here are the techniques that actually move the needle.
Resize dimensions first
This is the single most effective step. If your website displays images at 1200 pixels wide, there is no reason to serve a 4000-pixel original. Resizing from 4000px to 1200px width reduces the pixel count by about 90%, and the file size drops proportionally. Most viewing contexts — web pages, social media, email — do not benefit from extremely high-resolution images.
Choose the right format
Format choice has a massive impact on file size. A photograph saved as PNG might be 8 MB; the same image as JPG at 85% quality is typically 300–500 KB. For web use, WebP often beats JPG by another 25–30%. If your current workflow exports everything as PNG by default, simply switching to JPG or WebP for photographs will cut file sizes dramatically.
Adjust quality settings
JPG quality settings are a direct lever on file size. At 95% quality, files are large and visually indistinguishable from the original. At 80%, file sizes drop by 50–60% with minimal visible difference. Below 70%, compression artifacts start becoming noticeable in areas with smooth gradients and fine detail. For web use, 75–85% is the practical sweet spot.
Strip metadata
Photos carry EXIF data — camera model, GPS coordinates, shutter settings, thumbnail previews. This metadata can add 50–200 KB per image. Stripping it reduces file size and removes potentially sensitive location information. Most web-focused image tools do this automatically.
Use the right tool for the job
Batch processing is essential when you have more than a handful of images. Manually adjusting quality settings for 50 photos is tedious and inconsistent. A good image compression tool lets you set your target quality and dimensions once, then applies them across all files at once.
Recommended targets
- Web hero images: 150–300 KB, max 1920px wide
- Blog inline images: 80–150 KB, max 1200px wide
- Thumbnails: 20–50 KB, 300–400px wide
- Social media: 200–500 KB, platform-recommended dimensions