What is the minimum & maximum amount of transaction that i can charge via Midtrans?

For credit card payment, the minimum amount that could be processed by Midtrans is IDR 10,000, and the maximum amount is IDR 999,000,000.

However please note that there is Fraud Detection System that will be warned when there is a transaction passing certain amount of money.

Don't forget that we could not process currency other than IDR and we could not process currency using decimals. Read it here.