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Rate limiting rules

Rate limiting rules allow you to define rate limits for requests matching an expression, and the action to perform when those rate limits are reached.

​​ Rule parameters

Like other rules evaluated by Cloudflare’s Ruleset Engine, rate limiting rules have an associated expression and an action.

The expression specifies the criteria you are matching traffic on using the Rules language. The action specifies what to perform when there is a match for the rule and any additional conditions are met. In the case of rate limiting rules, the action occurs when the rate reaches the specified limit.

Besides these two parameters, rate limiting rules require the following additional parameters:

  • Characteristics — The set of parameters that define how Cloudflare tracks the rate for this rule.
  • Period — The period of time to consider (in seconds) when evaluating the rate.
  • Requests per period — The number of requests over the period of time that will trigger the rate limiting rule.
  • Mitigation timeout — Once the rate is reached, the rate limiting rule blocks further requests for the period of time defined in this field.

Refer to Rate limiting parameters for more information on mandatory and optional parameters.

Refer to Determining the rate to learn how Cloudflare uses the parameters above when determining the rate of incoming requests.

​​ Important remarks

Applying rate limiting rules to verified bots might affect Search Engine Optimization (SEO). For more information, refer to Improve SEO.


​​ Availability

Rate limiting rules are available to all customers. The available features depend on the exact plan:

FeatureFreeProBusiness or Enterprise1Enterprise with WAF EssentialEnterprise with Advanced Rate Limiting
Available fields
in rule expression
Path, Verified BotHost, URI, Path, Full URI, Query, Verified BotHost, URI, Path, Full URI, Query, Method, Source IP, User Agent, Verified BotStandard fields, dynamic fields (including Verified Bot), other Bot Management fields2Standard fields, dynamic fields (including Verified Bot), other Bot Management fields2, request body fields3
Counting characteristicsIPIPIPIP, IP with NAT supportIP, IP with NAT support, Query, Host, Headers, Cookie, ASN, Country, Path, JA3 Fingerprint2, JSON body field, Body
Available fields
in counting expression
N/AN/AAll rule expression fields, Response code, Response headersAll rule expression fields, Response code, Response headersAll rule expression fields, Response code, Response headers
Counting modelNumber of requestsNumber of requestsNumber of requestsNumber of requestsNumber of requests,
complexity score
Maximum sampling period10 seconds60 seconds10 minutes1 hour1 hour
Maximum timeout period10 seconds1 hour1 day1 day1 day
Number of rules125100100

1 Enterprise plans with no additional subscriptions.
2 Only available to Enterprise customers who have purchased Bot Management.
3 Availability depends on your WAF plan.

​​ Next steps

You can configure rate limiting rules at the zone level and at the account level, depending on your plan and product subscriptions.

To configure rate limiting rules in the Cloudflare dashboard, refer to the following resources:

You can also configure rate limiting rules using the Rulesets API. Refer to Create rate limiting rules via API for more information.