Polkadot, Cosmos, Avalanche, Solana & Cardano Compared 2025

TL;DR: Polkadot, Cosmos, Avalanche, Solana, and Cardano are some of the most promising blockchains in 2025, demonstrating each blockchain’s hundred paths to a solution to the blockchain trilemma, scalability, security, and decentralization.

This article compares them side by side and explores their architecture, transaction speed, consensus, block times, and ecosystem.

Here is a quick at-a-glance comparison:

Different blockchains excel in different categories:

• Each blockchain pair with multi-chain flexibility and interoperability can be found in Polkadot and Cosmos.
• The fastest blockchain transactions and overall performant blockchain is given to Avalanche and Solana.
• Cardano is focused on security, governance, and developing real-world use cases at a slower pace, but with painstaking care.

Diving into the full comparison below to see which blockchain wins in each category in 2025!

1. Blockchain Structure: Monolithic vs Multi-Chain – Who Does It Best?

When it comes to modern blockchain construction, the ways in which they are built under the hood is arguably their biggest differentiation. Some blockchains embrace simplicity through what is called a monolithic approach, which means a single chain does all the heavy lifting. Other blockchains choose a multi-chain or modular approach, which in turn means many chains working in unison, each one used for different roles.

In this section, we will describe the architecture of Polkadot, Cosmos, Avalanche, Solana and Cardano – illustrating their unique approaches to multi-chain technologies and how each relates to scalability, performance and flexibility.

Architecture Comparison Table

Polkadot the Multichain Powerhouse

Polkadot is designed to embody a polylithic blockchain architecture. This means it has a Relay Chain enabling multiple parallel processing parachains.

Each parachain is its own blockchain, however all parachains plug into Polkadot’s Relay Chain which manages security and finality, hence by distributing the work across many parachains, each of which can have parallel processing, Polkadot can theoretically handle millions of transactions per second.

Polkadot 2.0 is also introducing Elastic Coretime which is an optional term for developers to hire a flexible amount of space on the network – important for on-demand scaling.

👉 Learn more about the architecture of Polkadot 2.0.

Cosmos: the Internet of Blockchains

Cosmos employs a similar multi-chain approach but instead of a single Relay Chain, Cosmos features a Cosmos Hub enabling many independent zones (blockchains) to operate through the IBC Protocol (Inter-Blockchain Communication Protocol).

Zones operate in complete sovereignty, with their own validators, rules, and governance, while simultaneously allowing for token and data transfers anywhere in the ecosystem.

👉 Explore the Cosmos Ecosystem.

Avalanche: Subnets for Customization

Avalanche has adopted a multi-chain model as well; where they allow subnets.

By default, Avalanche contains three chains (X-Chain handles assets, C-Chain handles EVM smart contracts, and P-Chain handles metadata), but they also allow for the launching of custom subnets by anyone on the EVM and Avalanche protocols.

Subnets are flexible; they can be public, private, or even regulatory-compliant and enable any and all of the capabilities of the Avalanche consensus (called Snowman); which fast tracks improvement for developers and organizations working in the Avalanche ecosystem.

👉 More about Avalanche subnets.

Solana: The High Speed Monolithic Beast

Solana does it a little differently. Instead of a multichain or subnets, Solana is pure monolithic.

In fact, everything in Solana is done on a single chain, but due to Solana’s way of implementing Proof of History (PoH) and then Tower BFT as a design, Solana can do parallel-processing within one chain.

This simplicity is one reason Solana is so incredibly fast and cheap, but that also means the network is forced to use the same chain for everyone’s activity, causing congestion during peak use times.

👉 See how Solana works.

Cardano: Secure and Monolithic by Design

Cardano is also a monolithic blockchain architecture, however it is focused heavily on security, formal methods and sustainability.

Unlike others discussed, Cardano builds on 2 separate layers (Settlement Layer and Computation Layer) both of which operate on 1 chain.

Cardano does not utilize built-in sharding or parachains, however Cardano is also working on developing Layer 2 solutions like Hydra for off-chain scaling with a clean main chain.

👉 Cardano’s official documentation.

Ranking: Top blockchain architectures for flexibility / scalability

• # 1 Polkadot – Extremely modular, made for scalability with a shared security model.
• # 2 Cosmos – Extremely flexible but chains are responsible for their own security.
• # 3 Avalanche – Good balance of the convenience of EVM and custom subnets for enterprises and dApps.
• # 4 Cardano – Highly secure and clean layer but layer 1 dependent; most of the scaling is at layer 2.
• # 5 Solana – Extremely monolithic but optimized for speed with a level of simplicity that lacks flexibility.

2. Transaction Throughput (TPS): Which Blockchain Is the Fastest?

When discussing blockchain performance, transaction throughput (TPS) is easily one of the most discussed metrics. TPS is important because it reflects how many transactions a blockchain can execute per second, and that is important for user experience, DeFi, gaming, and any real world application that requires high speed settlements.

That said, TPS isn’t the whole picture, it is also crucial to recognize if the TPS speeds are theoretical maximums or actual real world performance.

Let’s breakdown Polkadot, Cosmos, Avalanche, Solana and Cardano side by side.

Transaction Throughput Comparison Table

Polkadot: With the goal of 1 Million TPS

Polkadot is designed for extreme scalability and has the theoretical upper limit capability of 1 million TPS. So, how can Polkadot achieve this? Polkadot parachains operate concurrently to process transactions simultaneously, and with new changes such as asynchronous backing, Polkadot has reduced block times and increased throughput by 5-10 times its predecessor.

It is important to recognize that this is a theoretical number based on active parachains.

Cosmos: Consistent TPS, multiplied by many chains

Generally, cosmos chains will average several hundred TPS for each chain via tendermint consensus mechanisms.

Cosmos networks scale horizontally because each zone (blockchain) operates independently, which means the sum of all active zones theoretically could provide very high ecosystem wide throughput capability. Still, per chain TPS lags relative to other chains like Avalanche or Solana.

Avalanche: Fast and flexible

Avalanche’s C-Chain, EVM compatible, sits at about 4,500 TPS at present, which puts it amongst the fastest smart contract chains at present. Avalanche can create “subnets” and consequently will scale horizontally with an infinite number of custom blockchains, each developable for high TPS levels. Future technical upgrades aim to push Avalanche TPS beyond 20,000.

Solana: The speedy king of single chains

Solana is famous for its speed, peaking at approx 65,000 TPS, largely due to its proprietary Proof of History and optimizations for parallel transactions.There are many times, in real world use cases, Solana will show average thousands TPS, and burst however it is still currently, the fastest Layer 1 blockchain in real operating conditions.

Cardano: Long game of TPS

Cardano is currently capable of approximately 250 TPS on the main Layer 1, which is about to get a whole lot ambitious, aiming for over 10,000 TPS with it’s Ouroboros Leios upgrade projected for 2025-2026. Additionally, Hydra (Layer 2) network allows for an off chain scaling capability of 1,000 TPS per head, while providing security to Layer 1, thus scaling Cardano network.

Ranking: Fastest Blockchain in 2025 (TPS Focus)

1. Polkadot – Theoretical leader in TPS thanks to parachain parallelism.
2. Solana – Proven highest single-chain TPS in live conditions.
3. Avalanche – Fastest among EVM-compatible chains, with potential to scale via subnets.
4. Cosmos – Scalable by design, but per-chain TPS is lower.
5. Cardano – Currently slowest, but major upgrades (Leios, Hydra) aim to close the gap in 2025-2026.

3. Consensus Mechanisms: How These Blockchains Stay Secure and Decentralized

Every blockchain requires a means for members on the network to come to consensus over transactions and secure the network, which is known as the consensus mechanism of the blockchain. Polkadot, Cosmos, Avalanche, Solana, and Cardano use different forms of Proof of Stake (PoS) each do this in different ways, presenting different trade-offs in the levels of security, decentralization, and speeds. Let us review each.

Consensus Mechanism Comparison Table

Polkadot: Nominated Proof of Stake (NPoS)

In Polkadot, members hold DOT and subsequently nominate validators that they would like to produce the blocks in their chain and perform the staking securing the network.

Polkadot is a hybrid system, where they utilize:

• 1. BABE (Blind Assignment for Blockchain Extension) for block production
• 2. GRANDPA (GHOST-based Recursive Ancestor Deriving Prefix Agreement) for finality.

The hybrid system of BABE for block production ensures that fast block time operations are provided with strong finality from GRANDPA for all of the parachains. Polkadot 2.0 also has multiple upgrades, such as asynchronous backing, that provide great efficiencies in the overall system’s performance.

Cosmos: Delegated Proof of Stake with Tendermint BFT

The Cosmos chains are designed to use Tendermint BFT, which is a Delegated Proof of Stake (DPoS) system where token holders delegate ATOM to validators who propose and produce blocks. The Cosmos validators take turns proposing blocks where finality is immediate when 2/3 of the validators agree, thus also providing instant finality.

Avalanche: Avalanche Consensus (Snowman Protocol)

Avalanche differs than traditional BFT voting with its own Avalanche Consensus Protocol.

Avalanche validators simply use repeated random sampling (think voting to achieve consensus by gossiping with one another) to reach consensus very rapidly. Avalanche can also operate leaderless, is highly scalable, and allow sub-second finality with thousands of validators.

Solana: Proof of History + Tower BFT

Solana uses a hybrid consensus with Proof of History (PoH) combined with Tower BFT.

PoH is used as a cryptographic clock ordering transactions that users start submitting to the blockchain (without all validators needing to communicate with one another); Tower BFT uses proof of stake as a voting process that allows blocks to be finalized with sufficient confidence after a handful of confirmations. The overall consensus model allows very fast block times (~0.4 second), quick finality though performance hardware is required and assumed when validators will be online.

Cardano: Ouroboros Proof of Stake

Cardano also is using and is developing with the Ouroboros family of protocols which has been peer reviewed and mathematically proved secure. In Cardano, validators (stake pool operators) are randomly chosen to produce blocks in some time slot, while a deposit of staked, or delegated stake, determines the leaders, thus acting as a lottery.

In probabilistic finality nature for Cardano (like Bitcoin) there are added finality and certainty for each confirmation. Upcoming versions like Ouroboros Leios will introduce segregated input endorsers, that allows Cardano to submit many transactions through a single consensus structure (protocol), and thus potentially greater throughput without degrading overall security.

Ranking: Best Consensus for Speed, Decentralization & Security

• Fastest Finality:
  1. Avalanche
  2. Solana
  3. Cosmos
  4. Polkadot 2.0
  5. Cardano
• Most Decentralized Validator Set:
  1. Cardano (3,000+ stake pools)
  2. Cosmos (175+ validators per chain)
  3. Avalanche (thousands of validators possible)
  4. Solana (hundreds of high-spec validators)
  5. Polkadot 2.0 (limited validator slots, but nominators increase participation)
• Most Secure by Design (Research-backed):
  1. Cardano (peer-reviewed, mathematically secure)
  2. Polkadot 2.0 (formalized, robust hybrid consensus)
  3. Cosmos (simple and proven Tendermint)
  4. Avalanche (novel approach, highly scalable)
  5. Solana (speed prioritized, but more centralized hardware requirements)

Block Time & Finality: How Fast Do Transactions Settle?

Block time is the regularity at which new blocks are generated on a blockchain. Finality is when a transaction is confirmed and immutable. Both are important for user experience and use cases in the real world, such as DeFi trading, gaming, or payments.

Let’s see how Polkadot, Cosmos, Avalanche, Solana, and Cardano compare in terms of block speed and transaction finality.

Block Time & Finality Comparison Table

Ranking: Best Blockchain for Block Time & Finality

1. Cardano – Slowest block time (~20s) and longest time to certainty (~minutes), but highly secure.
2. Avalanche – Sub-second finality and ~1s block time.
3. Solana – Fastest block production (~0.4s), with ~2-3s finality.
4. Cosmos – Slower blocks (~6s), but instant finality per block.
5. Polkadot – Faster than before (~6s blocks), but finality takes a bit longer.

5. Developer Ecosystem & Use Cases: Where Are the Projects and Opportunities?

Developer Ecosystem & Use Cases: What are the Projects and Opportunities? The success of a blockchain doesn’t come down to speed or scalability alone but also the developer-friendly ecosystem, usability, and willingness to build real-world projects.

Let’s take a look at Polkadot, Cosmos, Avalanche, Solana, and Cardano in terms of developer friendly ecosystem, tooling and usage cases.

Developer Ecosystem & Use Cases Comparison Table

Ranking: Best Blockchain for Developers & Use Cases

1. Cardano – Secure and real-world focused, but more complex and slower ecosystem growth.
2. Avalanche – Easiest for EVM devs, plus subnets offer flexibility.
3. Solana – High-performance apps thrive, though Rust learning curve exists.
4. Cosmos – App-specific chains with IBC power, great for custom projects.
5. Polkadot 2.0 – Advanced but niche; best for teams wanting their own chain.

As we have noticed, they each have different strengths and weaknesses, as well as different areas of focus. Polkadot, Cosmos, Avalanche, Solana, and Cardano all serve different purposes.

There’s no one-size fits all solution each blockchain offers advantages over another depending on your objectives – speed, level of decentralization, security, interoperability, developer flexibility, etc.

So, let’s take a look at the final summarized rankings, based on all the key categories: Which is the best blockchain for you?

If your priorities are ultra fast transaction speeds and a high volume of trading at any cost:

✅ Solana or Avalanche

If you are an organization that wants to create your own blockchain or an organization that needs cross-chain interoperable capabilities:

✅ Polkadot 2.0 or Cosmos

If you want to build DeFi, NFTs, & Web3 applications that require blockchain tooling similar to Ethereum:

✅ Avalanche (EVM compatible)

If you desire ownership of real world identity, governance, and long term concept projects that need to be secure (ex. paying taxes, gamification, regulatory compliance, identity, etc.):

✅ Cardano

If you are an organization that requires customized chains that are legally compliant or need to be private:

✅ Avalanche Subnets or Polkadot Parachains

Final Thoughts

As we move into 2025, the blockchain space will be the most nuanced it has ever been. There will not be a singular ‘right’ answer – because the right option will ultimately depend on your project goals, developer preferences, and user experience and user interface objectives.

👉 Always do your own research (DYOR), keep on top of network upgrades/ releases, and think about ecosystem health, developer activity and adoption when evaluating blockchains.