There are many factors to consider when trying to determine which one is good for beard growth, a razor blade or a trimmer. The most important factor is the thickness of your beard. If you have a very thick beard, then a razor blade will probably give you the best results. However, if you have a thinner beard, then a trimmer might be the better option. Another factor to consider is the amount of time you want to spend on your beard each day. If you only have a few minutes to spare, then a trimmer will probably be quicker and easier to use. However, if you're willing to spend more time on your beard, then a razor blade will give you a closer shave and more control over your look. Ultimately, the best option for you depends on your individual preferences and needs.