Blockchains and the Scalability Concern

The issue of blockchain scalability is probably the one that raises its head most often, alongside regulation. Depending on the method of consensus, block size (if applicable) and underlying technologies being used, blockchain speeds — transactions per second or ‘tps’ — have been reported from anywhere between 2tps and theorized millions of tps. Scalability is the biggest selling point of alternatives protocols to Bitcoin and Ethereum. It is almost certain, there will be a trade off in one area (security, decentralization, computing power or other) when trying to dramatically improve scalability.

Current transaction speeds

Transaction speed may vary depending on network conditions. What we have listed here is average transaction speed in minutes for confirmed transactions in the first block after it was sent.

  • Bitcoin transaction speed on average is 78 minutes.
  • It’s limited to just 3tx per second through an artificial block size.
  • You can increase it by 100tx per second and not run into your computer’s limit.
  • Today, Bitcoin fees are rising and even if the blocks are becoming full, transactions are not quickly receiving confirmations.
  • Bitcoin currently has a 1MB block size limit.
  • Ripple transaction speed on average is 4 seconds.
  • The daily transactions on its network have increased in the past 6 weeks from 160,000 to over 1 million.
  • Their XRP Channel Payment’s scalability level is the same as Visa.
  • The company aims to change the traditional solution for financial payments.
  • Bitcoin Cash transaction speed on average is 60 minutes.
  • It has a block size limit of 8MB.
  • Exchanges have acquired confirmations in high numbers on deposits because Bitcoin Cash is prone to a double spend attack.
  • Awfully long delays are experienced because of issues on its security and stability.
  • Litecoin transaction speed on average is 30 minutes.
  • It has a 56tx per second maximum capacity.
  • Transaction verification is instant.
  • Transaction cost is very low.
  • Ethereum transaction speed on average is 6 minutes.
  • When it comes to block generation time, it is considered to be the fastest cryptocurrency in the world.
  • Its maximum capacity on earlier tests showed it reached 25tx per second.
  • The maximum gas that can be processed by an individual node is limited.
  • Its scalability has had improvements with Sharding and PoS.
  • Nano transaction speed takes on average 5 seconds.
  • It uses the Block Lattice technology.
  • Transactions cost nothing.
  • Nano offers unlimited scalability.
  • EOS transactions take on average 1.5 seconds.
  • The EOS network handles up to 50,000 txs per second.
  • EOS has low transaction fees.
  • The network is highly secure and scalable.
  • Dash transaction speed on average is 15 minutes.& Currently, it has a 28tx per second limitation.
  • 2MB block size change limitation that allows up to 56tx per second.
  • Built to enable faster transfers.
  • Tron transaction speed on average is 5 minutes.
  • The Tron network handles 1500 txs per second.
  • Transaction costs are extremely low for Tron payments.
  • It has high scalability and numerous use cases.
  • Cardano transaction speed on average is 5 minutes.
  • Every transaction comes with a proof of legitimacy.
  • Each node on their network accepts and verifies transactions.
  • Iota transaction speed on average is 3 minutes.
  • No transaction fees and scaling limitations.
  • The more you throw at Iota, the fast it’ll get.
  • You have to confirm 2 previous to transmit your current transaction.
  • Zcash transaction speed on average is 15 minutes.& It has a blocksize of 2MB.
  • Zcash has pretty low transaction fees.
  • The Zcash network offers tight privacy and security.
  • Monero transaction speed on average is 30 minutes.& It has one of the most dynamic block sizes.
  • It can theoretically handle 1,000tx per second using a modern hardware and if the bandwidth will allow it.
  • Vechain transaction speed on average is 6 minutes.
  • It does not have a block size limit since it’s a dApp.
  • Vechain’s transaction fees are extremely low.
  • The Vechain network can handle up to 10,000 txs per second.
  • Nem transaction speed average is 30 seconds.
  • On an experiment done, it had a transaction average rate of 3,085.77tx per second in less than 1 hour.
  • It currently has 10.8 million accounts and into sequence transactions over a steady stream of transactions, they use a written application.
  • Stellar transaction speed average is 5 seconds.
  • Transaction cost is very low at 0.00001 lumens on every transaction.
  • Validating node is easier to run.
  • It has a distributed exchange.
  • Neo transaction speed average is 15 seconds.
  • It does not run on PoW but its PoS protocol is more streamlined.
  • It can do 1,000tx per second and maximum of 10,000tx per second.

Blockchain Trilemma

The ‘Scalability Trilemma’ is a term coined by Ethereum founder Vitalik Buterin that addresses the problem of how to develop a blockchain technology that offers scalability, decentralization and security, without compromising either one.

Why isn’t the blockchain scalable?

In order to scale, the blockchain protocol must figure out a mechanism to limit the number of participating nodes needed to validate each transaction, without losing the network’s trust that each transaction is valid.

  1. Since every node is not allowed to validate every transaction, we somehow need nodes to have a statistical and economic means to ensure that other blocks (which they are not personally validating) are secure.
  2. There must be some way to guarantee data availability. In other words, even if a block looks valid from the perspective of a node not directly validating that block, making the data for that block unavailable leads to a situation where no other validator in the network can validate transactions or produce new blocks, and we end up stuck in the current state. (There are several reasons a node might go offline, including malicious attack and power loss.)
  3. Transactions need to be processed by different nodes in parallel in order to achieve scalability. However, transitioning state on the blockchain also has several non-parallelizable (serial) parts, so we’re faced with some restrictions on how we can transition state on the blockchain while balancing both parallelizability and utility.


Scaling the blockchain is a known challenge and has been an active area of research for several years. SegWit (Bitcoin-only), Off-chain state channels, Sharding, Plasma, Off-chain computations, Proof of stake, Blockchain rent, decentralized storage service or Lightning are attempts to fix scalability issues.



Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store
IWS FinTech

IWS FinTech

IWS consults on and develops disruptive technologies such as FinTech or Blockchain (project management/product).