Estimate transit crowding by time.
Rail crowding is measured two ways and they tell different stories. Load factor against total capacity is the headline number operators publish, but total capacity already assumes a dense standing crowd, so a train at 90% load factor is nowhere near comfortable. The figure that matches lived experience is standing passengers per square metre of standing area: below 2 you can move, 4 means continuous body contact, and 6 or more is crush loading where the doors close on people. This calculator reports both, because a 125% load factor sounds alarming and a 3.2 per square metre figure tells you what it actually feels like.
Crowded Train Checker
Total capacity = seated + standing; load factor = passengers / total capacity x 100; standing = passengers - seated; density = standing / standing area
Anything above about 90% means most people are standing, and above 100% means the train is beyond seated-plus-comfortable-standing. Look at standing density rather than load factor for how it will feel.
Four is the usual planning figure for peak standing, six is crush loading, and eight is physically possible but unsafe. Anything above four makes it hard to reach the doors.