Acceptable Use Policy

This policy covers how you may use macaddresslookup.app, including the website, the bulk data files, and the public API. It exists to keep a free service usable for everyone.

The principle

Use the site the way a reasonable person would: look things up, build something useful on the API, download the data you need. Do not degrade the service for others, and do not use it to cause harm.

Load and automated access

The API is rate limited per IP address. You may not circumvent those limits by rotating through addresses, distributing requests across many clients, or any similar technique.

If you need more than occasional lookups:

• Cache responses. The registry changes at most once a day, so a cached answer stays correct.
• Use the static data files under /data/ instead of the API. They are the same data, they are not rate limited, and one small cached file answers every lookup for that prefix.
• For very large workloads, download the bulk XML export or take the registry directly from the IEEE.

Crawling the entire site page by page to rebuild the database is not acceptable use. The data is freely available in bulk; take it that way.

Prohibited activity

You may not use this site or its data to:

• Attack, disrupt, or degrade the service, including denial of service attempts, resource exhaustion, or probing for vulnerabilities without permission.
• Gain or attempt to gain unauthorised access to any system, account, or network, whether ours or anyone else's.
• Track, profile, identify, or locate individuals. Registry data identifies organizations that registered address blocks; using it to target people is a misuse of it.
• Support unauthorised network intrusion, device spoofing intended to defeat access controls, or evasion of security measures you are not authorised to bypass.
• Break any applicable law, infringe intellectual property, or facilitate fraud.
• Misrepresent the data as official IEEE output, or present this site as affiliated with the IEEE.

Security testing

Do not run vulnerability scanners, fuzzers, or penetration tests against this site without written permission. If you find a security problem, report it to [email protected] and give us a reasonable chance to fix it before disclosing it publicly. Reports made in good faith are welcome and will not be met with legal threats.

A note on MAC address spoofing

Changing the MAC address of a device you own is legitimate and common: it is what modern phones do by default, and our generator exists partly to help with it. Using a spoofed address to impersonate someone else's device, defeat network access controls you are not authorised to bypass, or obtain a service you are not entitled to is not legitimate, and this site may not be used in support of it.

Enforcement

We may block addresses, throttle traffic, or withdraw access at any time, with or without notice, where we believe this policy has been broken. Where activity appears unlawful we may report it to the relevant authorities.

Reporting misuse

If you see the service being abused, tell us at [email protected].