I usually wear a different kind of deodorant. I ended up this one by mistake from our local grocery delivery. I did not want to deal with returning it, so I decided to try it. I did find out that this is twice the price I usually pay for the one I usually buy. That did not make me happy and I thought that this better work really well for that price. So, this became a quest actually. I decided to test out the "24 hour" guarantee. It does work for 24 hours, in fact it worked for over 48 hours. I can not tell you what hour it stopped working, but by 72 - it was not working! I have to be honest and say that I do not work hard enough to actually sweat - so I can not tell you that it worked after really putting it to the test. But for a normal day - it worked for longer than 24 hours. The stuff I was using before boasted the same thing.