How do you convert US dollars to pesos?

First you need to know which country's pesos are being converted. Several countries use currency called a peso but they have different values, in the same way that the US, Canada, Australia, and New Zealand all use money called "dollars" but with different values.

Once you have the country, you should find a site that posts conversion factors. Exchange rates change every day so any answer posted here would be out of date almost immediately. While it's not normal WikiAnswers policy to say "use the internet", that's the best approach in this case. You can check a site such as www.xe.com, CNNMoney, etc. for the latest conversion factors.