Solana Priority Fees and Compute Units: How to Set Them

On Solana you pay two things: a base fee of 0.000005 SOL for every signature, and an optional priority fee that buys a better place in the queue. The priority fee comes from two numbers you can set. The compute unit limit is how much processing work you book for your transaction, and the compute unit price is how much extra you offer for each of those units. Multiply them together and that is the priority fee.

What a compute unit is

A compute unit measures work, the way a kilowatt-hour measures electricity. A plain SOL transfer uses very little of it. A swap routed through several pools on Jupiter uses a lot. By default each instruction is allowed 200,000 units, and one transaction can ask for at most 1.4 million. Book too few and the transaction stops halfway with an out-of-compute error. Book far too many and you simply pay for the booking, because you are charged for what you request rather than what you use.

How the two numbers become a fee

The compute unit price is quoted in micro-lamports - millionths of a lamport, and a lamport is a billionth of a SOL - which is why the numbers look enormous while the amounts stay tiny. Book 200,000 units at 10,000 micro-lamports each and the priority fee is 2,000 lamports, or 0.000002 SOL. Think of a courier: the limit is the size of the parcel, and the price is what you add per kilo to jump the queue.

Setting them without writing code

Most people never touch the raw numbers. In Phantom the transaction settings offer normal, fast and turbo, and each step raises the compute unit price for you. Jupiter has the same idea in its swap settings, with an automatic option that reads recent network conditions and a manual cap if you want one. Raise it a notch when transactions start failing or hanging during a busy spell, and leave it alone the rest of the time.

Start at the lowest setting and move up only when something actually fails. During quiet hours the default lands fine and a turbo fee buys nothing you needed. Solana transaction fees explained breaks down everything you are charged, and how to fix failed Solana transactions covers the compute budget error when you meet it.