The Ultimate Image Compression Checklist Before Publishing

Every image you publish online should pass a few quick checks first — for speed, quality, SEO and accessibility. Here's a copy-and-keep checklist to run before anything goes live.

The pre-publish checklist

1. ☐ Right format for the content. Photo → JPG or WebP; graphic/logo/screenshot → PNG or lossless WebP; needs transparency → PNG or WebP, never JPG. (Format guide.)
2. ☐ Resized to display dimensions. Don't ship a 4000px image into an 800px slot. (Resize without distorting.)
3. ☐ Compressed to the visual sweet spot. Quality ~80 for photos; check the before/after preview. (How.)
4. ☐ Modern format where possible. WebP or AVIF for the web — 25%+ smaller.
5. ☐ Descriptive filename. blue-suede-shoes.jpg, not IMG_2831.jpg.
6. ☐ Meaningful alt text on every content image (accessibility + SEO). (Image SEO.)
7. ☐ Responsive variants via srcset so phones get smaller files.
8. ☐ Dimensions set (width/height) to prevent layout shift.
9. ☐ Lazy-load below the fold, prioritize the hero/LCP image.
10. ☐ Under a sensible weight. Aim for hero images well under ~200 KB.

The 30-second version

Right format → resized → compressed → named → alt text. Nail those five and you've handled 90% of what matters.

Where most people slip

• Skipping the resize. Compression alone can't fix a 4000px image in a small slot.
• Blind quality settings. Always eyeball the result, don't trust a number.
• Forgetting alt text. It's free SEO and required for accessibility.

Run the checklist now

The compression, conversion and preview steps all happen in one place — the free image compressor, right in your browser. For the deeper performance angle, see image optimization for web performance.