Question

Which of the following sizes are effective file sizes for large images on web pages?

20Kb to 30Kb

50Kb to 70Kb

80Kb to 100Kb

120Kb to 150Kb

Answer 1

Short answer: 50–70 KB and 80–100 KB are the most “effective” choices.

Why:
- 20–30 KB is usually too small for a true large image — it will often look over‑compressed and blocky at full width.
- 50–100 KB is a good sweet spot for large hero/feature images when properly compressed (JPEG/WebP/AVIF) and sized for the display — acceptable quality with reasonable download cost.
- 120–150 KB is usable but getting heavy — fine occasionally for very detailed or photographic heroes, but it will slow page load and should be avoided as the norm.

Tips:
- Use responsive images (srcset/sizes) to serve appropriately sized images for different viewports.
- Prefer modern codecs (WebP/AVIF) which often cut file size 30–70% vs JPEG.
- Use lazy loading for below‑the‑fold images.
- For Retina/2× displays, remember you may need larger pixel dimensions (and thus larger files) or use vector/SVG where possible.