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How to Calculate Bitcoin Transaction Size

How to Calculate Bitcoin Transaction Size
How to Calculate Bitcoin Transaction Size

How to Calculate Bitcoin Transaction Size welcome to one minute crypto Im your host Carlos and today I want to talk about the exact formula that goes into calculating how much you need to pay in fees on a Bitcoin transaction Ive seen a lot of posts recently celebrating hey I was able to pay so little in fees in my transaction confirmed so quickly but actually what people dont realize is that the fee is not dependent on the number of bitcoins you send its actually dependent on the size of the Bitcoin transaction and size is not bitcoins its the number of input and outputs that go into the transaction Im gonna give you the exact formula so you can calculate the size of your own transactions here in this article but first I want to thank our sponsor because this episode is proudly sponsored by Kiki a USB hardware wallet that plugs into your computer to keep your cryptocurrency safe this little guys stores your private keys directly on it so even if your computer gets a virus your funds are still secure check them out at Keep Calm so like I was saying the size of a transaction is based on the number of inputs and outputs now typically when youre sending a Bitcoin transaction youre only going to have one output because youre sending it to one person either yourself for a transfer or an exchange or another person or business but you actually need a second output youre typically gonna have two outputs because youre not sending all of the bitcoins that are involved in the transaction you need some as change take for example if youve got one Bitcoin in an address and you want to send point zero zero five you cant just send point zero zero five and have that be or one output the transaction needs to have all of the bitcoins accounted for so youre gonna have 0.005 going to the destination and then 0.995 the remaining amount going to a different destination that you control thats called the change dress so its very very common to have two outputs one for the person youre paying and one for yourself as a change address so now we know theres two outputs how many inputs are there gonna be well that just depends on how your bitcoins are spread out inputs do not mean source addresses it actually means source unspent transaction outputs for you TX OS which means every time youre paid Bitcoin thats one input so if you receive five payments youve got those in five different u TX OS if you want to go send that all at once your transaction has five inputs and thats gonna make a large transaction which costs more in fees so heres the exact formula its the number of inputs times a hundred and forty eight bytes now typically thats gonna be one or two inputs but if you have received a lot of Bitcoin at a lot of different times itll be more and then you add the number of outputs times 34 bytes now this is the bulk of the transaction the number of inputs number of outputs here being multiplied by these numbers makes up the huge majority of the size after youve done that you add 10 more bytes and then plus or minus the number of inputs in bytes so if youve got two inputs and two outputs thats 2 times 148 plus 2 times 34 plus 10 and then maybe youre gonna add two more for the two extra inputs thats because some input addresses are a little bit shorter than others and so you do have that slight variance but basically the number of bytes is hugely based on the number of inputs you can see that multiplier 148 is much bigger than the 34 multiplier so the best way to keep your fees down is to limit the number of inputs that youre using in the transaction if you have any questions feel free to post in the comments below the article Id love to help you out in any way I can Im Chronos thanks for watching

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