Can you help or suggest the formula for calculation of simple multisig transactions? I have an issue to calculate the size of multi signature 2-2 transaction. I tried to follow this: https://bitcoin.stackexchange.com/questions/30570/predict-multi-signature-transaction-size answer, however it is vague and unclear. Here is my calculations: pubKeySize = 33; sigSize = 72; n = (m = 2); sizeOfRedeemScript = 1 + n * pubKeySize + 2; sizeOfScriptSig = 1 + m * (1 + sigSize) + 2 + sizeOfRedeemScript; sizeOfInput = 32 + 4 + 2 + sizeOfScriptSig + 4; sizeOfScriptPubKey = 2 + /** what is the length of script?? */ len(script); sizeOfOutput = 8 + sizeOfScriptPubKey; sizeOfTx = 4 + 2 + sizeOfInput + sizeOfOutput + 4; If to be more precise I didn't get what is `SizeOfVarIntFor(lengthOfScript)` and what is the `len(script)` (how to calculate it?)