Compute Unit (CU)
Solana's unit of program execution cost. Every instruction consumes CUs, every block has a CU limit. Priority fees scale with fee-per-CU.
Compute Unit (CU)
Compute Units are Solana’s measure of program execution cost. Every instruction in a transaction consumes a specific number of CUs. Per block, a maximum CU limit is defined (as of May 2026, around 48 million CUs per block; Anza’s roadmap discusses a doubling to 100 million).
Who sets CU values
Program authors decide via their implementation how many CUs each instruction costs. The Solana runtime tracks consumption and stops a transaction once the per-transaction CU limit is exceeded.
Comparison: classic SPL Token vs P-Token
| Instruction | Classic | P-Token | Savings |
|---|---|---|---|
| Transfer | 4,645 | 76 | 98.4 % |
| TransferChecked | 6,200 | 105 | 98.3 % |
| MintTo | 4,538 | 119 | 97.4 % |
| Burn | 4,753 | 126 | 97.4 % |
Priority fees
Wallets can pay priority fees in lamports-per-CU to land in full blocks. Lower CU load per instruction (e.g. via P-Token) makes token transfers cheaper or creates headroom for more complex DeFi operations.
Deep dive
Pillars P-Token explained and Firedancer and Frankendancer.