Use the search engines of your choice to look for free IQ tests online. Search terms such as "free IQ test", "free IQ testing", "free IQ quiz" etc. Using several search engines and trying different search terms will return more results.
Try searching for other types of free IQ tests. For example,
spatial tests, which are supposed to be a good alterative for people who do not do well with verbal tests.
Narrow your search to specific tests, for example you could search for "free online IQ tests for kids", "free IQ test adult", "free certified IQ tests", "free genius IQ test" etc.
Consider looking for the Wonderlic test. This is a short IQ test that takes 12 minutes to complete. It is used mainly for employment purposes to match people to jobs. You can find these by searching "free Wonderlic test online".
Decide which tests work best for you, or take several for comparison purposes. Some web sites may require you to register and they will email you your test results, while others will give you an instant results upon completion of the free IQ tests online.