A usage limit is a quota that caps how much a service can be consumed during a defined period, such as requests per minute, compute hours per day, or tokens per month. Vendors use usage limits to separate normal use from heavy use, control cost, and keep shared systems stable under load.
In cyber security, usage limits are an important control against abuse. They help reduce brute-force attempts, API scraping, spam, and denial-of-wallet attacks that try to drain a victim’s budget by forcing excessive consumption. Defenders often pair limits with rate limiting, authentication, anomaly detection, and alerting so legitimate users can continue working while suspicious activity is slowed or blocked. In enterprise tools, limits also guide who gets baseline access and who needs higher-capacity approval.