How to use the image crop ratio guide
The frustrating part of posting a photo at a square or vertical ratio is that you cannot see what gets cut until it is already uploaded. Give this page your source width and height in px plus a target ratio, and it assumes a center crop and returns the area kept, the px cut away, the share of area lost and the crop coordinates. Pick a ratio from the list or type your own.
The math is a ratio comparison. If the source is wider than the target, the width is cropped; if it is narrower, the height is. The area kept is the largest box matching the target ratio within the shorter dimension, with px rounded to whole numbers. When the two ratios are identical the cut shows as exactly 0 px. Ratios are arithmetic, so they do not drift over time.
This tool deliberately carries no list of recommended per-platform pixel sizes. Those numbers get revised often, so baking a table in would go stale, and other Simplewoody guides already cover the lists (checked October 2026). What a list cannot tell you is how many px vanish from your own photo, and that is what this page computes. Off-center crops and automatic subject detection are not supported.
Frequently asked questions
Those numbers are revised often, so a table written today would be wrong within months. This page computes how many px actually disappear from your own source instead.
If the source ratio is wider than the target, the width is cropped; if it is narrower, the height is. When the two ratios match, the cut reads as 0 px.
Only center crops are calculated here. The total px removed is the same either way, so you can shift the whole amount to one side to work out a top- or bottom-anchored box yourself.