The only way you can know your HIV status is by taking an HIV test.
If you are sexually active, then it is better for you and your partner to know your HIV status.
HIV testing should be a routine part of looking after your sexual health. As is repeating the test every 6-12 months – or as appropriate, depending on your level of sexual activity and risk. This is important in case you are exposed to HIV in the future.
In the UK and many other countries, at least one-third of people living with HIV are not yet diagnosed.