A quick check before publishing a resized image
Read the dimensions
The downloaded dimensions should match the fit you intended. The width and height limits are ceilings, not a promise that both edges will equal the target values.
Review clarity
Small type may become difficult to read after a large reduction. Inspect the actual display size and consider a simpler image when fine detail no longer communicates well.
Check the receiving platform
A site may recompress your upload or make its own thumbnails. Keep a master image and compare the published result. This tool prepares a file; it cannot control what a third-party platform does to that file.
Try the workflow
A 3000 × 2000 image fitted inside a 1200 × 1200 box becomes 1200 × 800. The image stays in proportion; the box does not force a square crop.
Open proportional image resizer