Transactions Per Second (TPS)

What Is Transactions Per Second?

Transactions per second measures the throughput of a blockchain network. It’s the velocity at which transactions move from “pending” to “confirmed” and settled. A blockchain with 1 TPS can confirm only 1 transaction per second; a blockchain with 1,000 TPS can confirm 1,000.

TPS is constrained by the underlying architecture: block size, block time, and the number of transactions each block can contain. Bitcoin blocks are approximately 1 MB and are created every 10 minutes, limiting throughput to ~7 TPS. Ethereum blocks are larger and come faster (every 12 seconds), allowing ~15 TPS. Solana uses a different consensus model and can achieve tens of thousands of TPS, but at different trade-offs in decentralization and security.

Higher TPS is not inherently better — it comes with trade-offs. Networks that prioritize speed often sacrifice decentralization (fewer validators can keep up) or security (less time to verify transactions). This is known as the blockchain trilemma: speed, security, and decentralization cannot all be maximized simultaneously.

How Is TPS Measured and Constrained?

TPS is calculated by dividing the maximum number of transactions a block can contain by the average block time (in seconds). Here’s how it works in practice:

1. Block size limit: Bitcoin limits blocks to 1 MB. A typical transaction is ~250 bytes, so a block can contain approximately 4,000 transactions.
2. Block time: Bitcoin creates a new block every 10 minutes (600 seconds). So 4,000 transactions ÷ 600 seconds = ~6.7 TPS.
3. Network capacity: The result is Bitcoin’s maximum TPS. During high-demand periods, when the network is congested, transactions queue up and wait for blocks to include them — transaction fees spike as users bid against each other for inclusion.

Worked example: In December 2017, during Bitcoin’s surge to $20,000, the network became congested. Average transaction confirmation time increased from 10 minutes to 30–60 minutes. Average transaction fees spiked from $1 to over $50. This happened because Bitcoin’s 7 TPS limit was overwhelmed by demand — millions wanted to transact, but the network could only process 7 per second. Users with higher fees got priority, creating a “fee market” that priced out smaller transactions. Layer 2 solutions (Lightning Network, Stacks) were developed specifically to bypass this constraint by moving transactions off-chain.

Why Is TPS Important for Traders?

TPS directly affects user experience and adoption. A network with low TPS creates bottlenecks: long wait times and high fees. This limits the types of applications and users the network can support. Bitcoin, with 7 TPS, cannot support everyday payments like coffee purchases — the fees would exceed the transaction value. Ethereum, with 15 TPS, faced similar congestion during the 2021 DeFi boom, causing fees to spike to $50–100 per transaction.

Higher TPS attracts more users and developers. Solana’s 65,000 TPS (theoretical, not sustained in practice) enables a completely different ecosystem than Bitcoin’s 7 TPS — faster trading, lower fees, and support for high-frequency applications. However, Solana’s higher TPS comes at the cost of higher hardware requirements for validators, making the network more centralized.

For traders on PrimeXBT, TPS matters indirectly. When trading crypto on leverage, transaction confirmation speed can matter — a liquidation needs to hit the blockchain quickly to take effect. Networks with higher TPS like Ethereum have lower finality risk; networks with low TPS like Bitcoin have higher risk of reversal or unconfirmed transactions. Additionally, congested networks drive up gas fees (on Ethereum), which inflates trading costs for users moving assets on-chain.

TPS Across Different Blockchains

Key Takeaways

• Transactions per second (TPS) measures how many transactions a blockchain can process in one second — Bitcoin processes ~7 TPS while Solana processes ~65,000 TPS, reflecting fundamentally different architectural choices.
• Low TPS creates congestion: Bitcoin’s 7 TPS limit caused transaction fees to spike above $50 during the 2017 bull run, making everyday payments impossible.
• Higher TPS enables faster transactions and lower fees, but comes with trade-offs: Solana’s extreme TPS requires more computing power from validators, reducing decentralization compared to Bitcoin’s conservative 10-minute block time.
• Layer 2 solutions (Lightning Network, Polygon, Arbitrum) increase TPS by moving transactions off the main blockchain and only settling batches periodically, enabling thousands of transactions per second at lower cost.
• For traders, TPS matters for transaction finality: low-TPS networks have slower confirmation, while high-TPS networks enable faster liquidation or position changes, though at the cost of reduced decentralization.