Thickness tolerances vary by standard, width, thickness range, and rolling method (hot-rolled/cold-rolled).

Key points: - Cold-rolled plate tolerances are generally tighter than hot-rolled plate, and tighter still for thin plate. - Under the same standard, the greater the width, the larger the permissible deviation. - Negative-tolerance purchasing (commonly called "xia cha") is common in some markets, but it affects actual service strength and weight-based pricing.

Acceptance recommendations: explicitly cite the standard and tolerance grade, take multi-point thickness measurements on a sampling basis (at a certain distance from the edge), and agree on a dispute-handling method.