Transactions Per Second (TPS) is often treated as the definitive benchmark for blockchain throughput performance. But on Sui, TPS only tells part of the story. To truly understand Sui’s throughput, Commands Per Second (CPS) offers a more precise measure of the work being done onchain.
This distinction is why CPS appears not only in technical documentation but also in some blockchain explorers and dashboards. It’s increasingly used to give a clearer picture of network activity, especially as Sui continues to handle more complex, bundled transactions.
The need for CPS arises from how Sui handles transactions. Most transactions on Sui utilize Programmable Transaction Blocks (PTBs), which allow a single transaction to bundle together up to 1,024 separate operations, which on other chains would require multiple individual transactions.
The use of PTBs means a single transaction on Sui could represent tens, hundreds, or even a thousand individual actions, all executed atomically. If you were to compare that TPS directly to another chain that doesn’t support batching in the same way, the result would be a misleading, apples-to-oranges comparison.
Measuring real work with CPS
CPS captures the number of discrete operations the network processes each second, regardless of how many are bundled into a single transaction. CPS is surfaced on certain explorers and dashboards, offering a more detailed view into how much computation is being performed onchain. It’s a better reflection of what the network is actually accomplishing, especially important on a high-throughput chain like Sui.
By contrast, TPS simply counts the number of transactions completed per second, without regard to how complex or lightweight those transactions are. On many blockchains, a single transaction corresponds to a single action—like sending a token, authorizing a token approval, or minting an NFT. But on Sui, one transaction can perform dozens or even hundreds of actions at once. Measuring only TPS would vastly understate Sui’s real throughput and capabilities.
How PTBs reshape performance metrics
PTBs are a key innovation of Sui, enabling developers to group up to 1,024 operations into a single transaction. These operations can span a wide range of use cases, from asset transfers to composable smart contract calls, all within a single, atomic execution context. For users, this results in a smoother and more reliable experience: fewer transactions to sign, fewer failure points, and more predictable gas costs.
Developers also benefit from PTBs by being able to encode entire workflows into one atomic unit. This simplifies application logic and reduces latency, since multiple steps can be processed in a single transaction. In short, PTBs make it possible to do more with each transaction and CPS is the metric that reflects that added depth.
A better way to compare throughput
It’s common to see TPS charts used to rank blockchains, but without context, these comparisons are shallow at best. If one chain requires ten transactions to complete a task that Sui can handle in a single PTB, its TPS may appear higher, but the actual work completed is equivalent. CPS helps level that playing field by accounting for the number of real operations taking place. That’s why on Sui, both TPS and CPS are measured.
Measuring what counts
TPS might be the headline number, but CPS tells the real story. On Sui, where transactions are often rich, composable bundles of logic thanks to PTBs, CPS offers a much more meaningful look at what the network is doing. For developers, ecosystem analysts, and anyone comparing blockchain performance, understanding CPS is essential to understanding Sui.
As blockchains get more sophisticated, the way they are measured needs to evolve. CPS gives a clearer picture of what’s really happening under the hood, especially on a network like Sui where transactions do so much more. It’s not just about counting how fast things move—it’s about understanding the work getting done.
