Transaction Fees – What is the difference between sats/byte and BTC/KB?

Sats/byte stands for satoshi per byte and has long been the standard unit of transaction fees. When Segwit was deployed, a new fee called sats/vbyte was used for its transactions. This answer explains how to convert between bytes and vbyte.

Bitcoin Core uses BTC/KB, also called Bitcoin per kilobyte in some places. However, some parameters such as minrelaytxfee Internally stores fees in sats/KB. To get the sats/KB commission rate, simply divide the sats/byte value by 1000. 1 Kilobyte is 1000 bytes (there are other units that measure bytes as powers of 1024, but these are not used by the Bitcoin client).

Similarly, you can use the above procedure to convert sats/vbyte, also known as sats per virtual byte, to sats/vKB (sats per virtual kilobyte).

To get the sats/byte to BTC/KB (BTC per kilobyte) ratio, you need to divide the sats/byte value by 100000 (one hundred thousand). Because 1 sats/byte is equal to 0.00001 BTC/KB. On this Reddit post.