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What is a Compute Unit?
Suward charges by Compute Units (CU), not by request count. Here is what one CU buys you, why we picked this model, and how to think about it when sizing your usage.
Suward charges by Compute Units (CU), not by request count. Here is what one CU buys you, why we picked this model, and how to think about it when sizing your usage.
If you've shopped for an RPC provider in the last few years, you've seen "Compute Unit" pricing on most of the bigger names — Alchemy, Infura, QuickNode all use some variant. Suward's billing works the same way. This post explains what a Compute Unit (CU) is in our system, why we use it, and how to estimate your real-world cost.
One Compute Unit ≈ the work it takes to serve one cheap read. A call to eth_blockNumber or eth_chainId is 1 CU. A call to eth_call reading an ERC-20 balance is also 1 CU. A call to eth_getLogs over a 5,000-block range is more — somewhere between 50 and 200 CU depending on the result size — because the upstream node has to do meaningfully more work.
CU pricing is the way to align what you pay with what the system actually does on your behalf.
Per-request pricing works fine for a uniform workload. Five thousand eth_blockNumber calls is the same shape as five thousand eth_getBalance calls. But the moment you mix in a few eth_getLogs calls or debug_traceTransaction calls, the request-level cost diverges by 50–500×. Two providers can quote you the same per-request price and end up charging wildly different bills for the same workload.
CU pricing makes the math explicit. The doc page for every method shows the CU cost. You can estimate your monthly bill in 30 seconds with a spreadsheet.
Three inputs:
getBalance against an unsealed state trie node is cheap; a getLogs over a 10k-block range is not.We rebalance the CU table roughly every six months. The current values are at /pricing.
The free tier gives you 300,000 CU per month — enough for a typical hobby indexer or a small frontend that polls the chain every few seconds.
Paid plans run $0.50 per million CU at the entry tier and scale down at volume. A million CU sounds like a lot until you remember that an active mempool watcher subscribing via eth_subscribe to pending transactions can burn that in an afternoon.
The single-method bills add up faster than you'd expect. A back-of-envelope:
eth_getLogs per chain head, range 5,000 blocks, response 100 KB → ≈100 CU per scanIndexers are heavy. Most workloads don't look like that.
Three workloads where CU is a worse fit than a flat-rate alternative:
newPendingTransactions subscription on Ethereum mainnet emits 10–50 tx hashes per second. Per-message CU adds up fast. We offer subscription-based pricing for this case at the enterprise tier — same CU table, different bundle.eth_call simulation. Tx simulation workloads (MEV, AMM aggregators) spend most of their CU on eth_call with state overrides. The math still works, but the rate matters. Look at the volume tier before committing.eth_call + eth_getLogs + eth_blockNumber.That gives you a CU/month estimate that's usually within 2× of reality. Iterate from there.
Compute Units are how Suward charges for the work upstream chain nodes actually do, in proportion to what each method costs us. Cheap reads cost 1 CU. Heavy reads cost more. The doc page for every method tells you the number. Estimating your bill is a spreadsheet exercise, and the free tier covers most hobby projects without you needing to think about it.
See the live CU table on /pricing. For workload-specific questions, reach out — we're happy to help you size it.