Menu

Image Resolution Test — Which resolution is optimal?

This page shows the same DJI drone image (8064×6048 Master) in 9 different variations: 3× Featured (Header), 3× Gallery-Thumbnail, 3× Lightbox (Full).
Here's how to test:
  1. Compare the sharpness on Desktop (1440px) and Mobile (375px)
  2. Click on each image — Lightbox opens the full version
  3. Check: Are the edges sharp? Are drone details recognizable? Is the sky free of artifacts?
  4. Weigh up: sharpness vs. file size (smaller = faster page loading)
All images were compressed using TinyPNG. WordPress automatically generates WebP versions (from WP 6.1 onwards).

1. Featured / Header Image (Landscape 1,905:1)

Just like the header image displayed at the top of every blog post. Expected display viewport: Desktop ~1400px, Retina doubles that.
Image Resolution Test — Image 1
1600×840
File size: 380.5 KB
Click → Lightbox
Image Resolution Test — Image 2
2400×1260
File size: 499.2 KB
Click → Lightbox
Image Resolution Test — Image 3
3840×2016
File size: 1030.2 KB
Click → Lightbox

2. Gallery thumbnail (portrait 5:6)

The small gallery tiles within a blog post. Display width: approx. 330px on desktop, 160px on mobile. Retina displays require 2× = 660px or 320px respectively.
Image Resolution Test — Figure 5
500×600
File size: 81.0 KB
Click → Lightbox
Image Resolution Test — Figure 6
750×900
File size: 141.6 KB
Click → Lightbox
Image Resolution Test — Figure 4
1000×1200
File size: 238.0 KB
Click → Lightbox

3. Lightbox / Fullscreen (Landscape Full)

Opens when you click on a gallery image. Sharpness is paramount here — it MUST look perfect on all screens, including 4K displays.
Image Resolution Test — Figure 7
1600×1000
File size: 308.1 KB
Click → Lightbox
Image Resolution Test — Figure 8
2560×1600
File size: 627.6 KB
Click → Lightbox
Image Resolution Test — Figure 9
3840×2400
File size: 1153.8 KB
Click → Lightbox

My recommendation (before the test)

  • Featured: 2400×1260 — Retina-ready on desktop, mobile performance OK
  • Gallery: 750×900 — double the pixel density for mobile and desktop
  • Lightbox: 2560×1600 — sharp on 4K displays without mega loading times
Decide based on visual comparison — your eyes are more important than my recommendation.