Any bookmaker’s margin is essentially what they charge you for placing a bet. Sharp bettors will be aware of what a margin is and how to work it out but for those that don’t, a Margin Calculator will do the work for you.
Bookmakers make profit by inflating the implied probability of an outcome, which decreases the odds you receive. The margin, which will vary depending on the bookmaker, is the difference between real probability and the odds offered by the bookmaker.

If you don’t know how to work out a bookmaker’s margin, using a Margin Calculator is the easiest way to calculate the probability and margin for any two-way or three-way bet. Compare margins to other bookmakers and understand why serious bettors use one.