What Is a Rate Limit?

In a nutshell

A rate limit is a ceiling on how many requests are accepted: "this many within this time." Just as a ticket gate decides how many people can pass at once, it keeps a service from getting too crowded or being abused.

How social media APIs set limits

According to X's developer documentation, limits are set per type of request over windows such as 15 minutes or 24 hours, and there are limits per user and per app. When you go over, an error comes back with the response code 429 (Rate limits, as of October 2026).

Other networks have their own limits. Since the numbers change at each company's discretion, the basic approach is for the tool to be built to wait and try again when it hits a limit. On the user's side, too, posting or loading a large amount in a short time makes it easier to hit a limit. Spreading posts out over time, as scheduled posts do, is easier on both the limits and the people viewing your account. The social media API itself is explained on the API page.

Rate limits as login protection

Rate limits are used not only for APIs but also for login screens. An attack that tries passwords by brute force works by trying hundreds of times in a short period. If you cap the number of attempts, that attack stops being practical. Combined with two-factor authentication, it makes an account harder to take over even if a password leaks.

In SNS TOWN

SNS TOWN's login stops accepting attempts for a while after 5 failures with the same email address, or 20 from the same connection, within 15 minutes. If it hits a request limit while loading reactions or followers from X, it tries again on the next round. The overall login protection is explained in Account protection, and preparing for takeovers in How to protect an official account from takeover.