The age-old question is finally answered and it's all based on your relationship to the bride and groom.
I used to keep track of all of the wedding gifts we had given to our friends and family. This was mostly to make sure it was kept even amongst everyone so as to avoid an awkward moment when two couples realized they received two (possibly drastically) different amounts for their nuptials. I was constantly utilizing my handmade formula that weighted the value of our relationship, the estimated cost of the wedding per plate and what our personal out of pocket costs were. This was a lot of work and completely unnecessary. So instead, I have begun referring to this handy chart of what to gift and to whom broken out by the dollar amount.
Remember this is only a rough guide and you should only gift what you can comfortably afford. Your friend or family member will hopefully be grateful just for your presence and never hold you gift amount against you. These suggestions are per guest.
$50.00 - $100.00
These people are your acquaintances, coworkers and distant relatives. If you are more than just a coworker and spend extensive time outside drinking wine and pinning, then err on the higher end of this spectrum.
$100.00 - $150.00
Close friends fall into this category. These are your besties, your sisters from other misters, brothers from other mothers, your gal pals and your bosom buddies. It is very important to consider in this category what your personal expenditures for the wedding were whether they were travel or bachelor/shower related.
$150.00 - $200.00
Close relatives weddings' require you to dig a little deeper into your pockets. Although your gift doesn't have a direct correlation to how much you like the couple under the chuppah, it does unfortunately have some indication of how excited you how for their union. Never got into debt, but be sure to share the love with a little extra green for your close relative's wedding.