Usage Limits

Please note that if you violate the requirements detailed in Usage Limits your API key may be disabled for a period of time.

Usage restrictions

If you use the Safe Browsing APIs (v4) to warn users about unsafe web resources, the following restrictions apply:

  • Lookup API (v4): You can query up to 500 URLs in a single POST request.
  • Lookup API (v4) and Update API (v4): A single API key can make requests for up to 10,000 clients per 24-hour period.

We limit the number of clients you can support with a single API key. If you expect that more than 10,000 distinct clients per 24-hour period will request updates, you must request additional quota from the Google Developer Console. We review these requests and require a contact when applying for increased quota to ensure that our service availability meets the needs of all API users. There is no cost for use of this API. For more information about large deployments, please apply for additional quota using the link above and describe your business needs or find answers to common questions in the public Google Safe Browsing API group.

User warnings

If you use the Safe Browsing APIs (v4) to warn users about risks from particular webpages, the following guidelines apply.

These guidelines help protect both you and Google from misunderstandings by making clear that the page is not known with 100% certainty to be an unsafe web resource, and that the warnings merely identify possible risk.

  • In your user visible warning, you must not lead users to believe that the page in question is, without a doubt, an unsafe web resource. When you refer to the page being identified or the potential risks it may pose to users, you must qualify the warning using terms such as: suspected, potentially, possible, likely, may be.
  • Your warning must enable the user to learn more by reviewing information at for social engineering (phishing and deceptive sites) warnings, for malware warnings, and Unwanted Software Policy for unwanted software warnings.
  • When you show warnings for pages identified as risky by the Safe Browsing Service, you must give attribution to Google by including the line "Advisory provided by Google," with a link to the Safe Browsing Advisory. If your product also shows warnings based on other sources, you must not include the Google attribution in warnings derived from non-Google data.

Suggested warning language

We encourage you to just copy this warning language in your product, or to modify it slightly to fit your product (see Metadata for additional information that may apply).

For social engineering (phishing and deceptive sites) warnings:

Warning—Deceptive site ahead. Attackers on [site URL] may trick you into doing something dangerous like installing software or revealing your personal information (for example, passwords, phone numbers, or credit cards). You can find out more about social engineering (phishing) at Social Engineering (Phishing and Deceptive Sites) or from

For malware warnings:

Warning—Visiting this web site may harm your computer. This page appears to contain malicious code that could be downloaded to your computer without your consent. You can learn more about harmful web content including viruses and other malicious code and how to protect your computer at

For unwanted software warnings:

Warning—The site ahead may contain harmful programs. Attackers might attempt to trick you into installing programs that harm your browsing experience (for example, by changing your homepage or showing extra ads on sites you visit). You can learn more about unwanted software at Unwanted Software Policy.

For Android potentially harmful application (PHA) warnings:

Warning—The site ahead may contain malware. Attackers might attempt to install dangerous apps on your device that steal or delete your information (for example, photos, passwords, messages, and credit cards).

Age of data and usage

When retrieving data using the Safe Browsing APIs (v4) clients must never use data older than what is specified by the service. Specifically, a warning can only be shown if the following is true:

Important: Under no other circumstances may a warning be shown.

User protection notice

Our Terms of Service require that if you indicate to users that your service provides protection against unsafe web resources then you must also let them know that the protection is not perfect. This notice must be visible to them before they enable the protection, and it must let them know that there is a chance of both false positives (safe sites flagged as risky) and false negatives (risky sites not flagged). We suggest using the following language:

Google works to provide the most accurate and up-to-date information about unsafe web resources. However, Google cannot guarantee that its information is comprehensive and error-free: some risky sites may not be identified, and some safe sites may be identified in error.