Fees

Not by amount

A transfer of 10 euros costs just as much as one of 10,000, as long as both need the same space in the block. You pay for bytes, not for value, unlike a bank transfer abroad.

Why space is scarce

A block has a limited size. If not all waiting payments fit in, the price per byte decides who goes first. It is an auction for space, not a fee schedule.

sat/vB

The rate is given in satoshi per virtual byte. Your fee is that rate times the size of your transaction.

Fee = rate x size. The amount does not appear in it.

What makes a transaction large

Not the amount, but the number of inputs. Whoever has received many small amounts has to combine many of them, and every input costs space. A common payment comes to around 225 virtual bytes.

The waiting room

Whatever has no block yet waits in the mempool. Miners take from there what brings in the most per byte. A higher rate means going sooner. With an empty mempool the minimum rate is enough.

When it gets expensive

With a full mempool the rates rise. For small amounts the fee can then make up a noticeable share: on 20 euros sent with an 8 euro fee that would be forty percent.