What is a good teeth whiter?

One of the best ways to whiten your teeth is with 44% carbamide peroxide. This is the strongest percentage of carbamide peroxide that is legal, and you'll notice a difference within the first week or two of use. You can find it on websites such as Amazon for $7.51, but I recommend buying a new custom fit tray for more comfort when you use it. Do not let the carbamide peroxide touch your gingiva, as it is a bleaching agent that will cause burning and irritation. You should also buy a remineralisation gel to apply to your teeth once you're finished to prevent tooth sensitivity. Lastly, only use carbamide peroxide on your central incisors, lateral incisors, and cuspids, as these are the most noticeable teeth and using them on any other teeth would be superfluous.

If you're not in a rush to whiten your teeth, then you should experiment with Crest White Strips or Optic White mouth wash. You could also try using hydrogen peroxide, which can be just as effective as carbamide peroxide, although some people would find the effervescence slightly annoying.

Don't do lemon, lime, strawberries, bananas etc they have acid which ruin your enamel especially if you brush your teeth straight after. No toothpaste can make you have white teeth unfortunately. Maybe your dentist can help.

Lemon/lime and baking soda mixture