Overview
Starknet is a Layer 2 network for Ethereum built by StarkWare, an Israeli company co-founded by Eli Ben-Sasson, one of the inventors of the STARK cryptographic proofs that give the network its name. Its main network launched in 2021–2022, and the STRK token followed in February 2024 with a large airdrop.
Where Arbitrum and Optimism are “optimistic” rollups, Starknet is a zero-knowledge (ZK) rollup: instead of assuming transactions are valid, it proves it mathematically.
How it works
Starknet bundles thousands of transactions and produces a STARK proof, a short piece of math that proves every transaction followed the rules. Ethereum checks this proof, which is much cheaper than re-running all the transactions. Because validity is proven, withdrawals don’t need a week-long challenge period.
STARK proofs have two notable advantages: they need no “trusted setup” (a one-time secret that must be destroyed), and they rely on cryptography considered resistant to future quantum computers.
Apps on Starknet are written in Cairo, a language designed for provable programs. It is powerful but different from Ethereum’s Solidity, so apps can’t simply be copied over. Every Starknet wallet is also a smart account, which allows features like social recovery and paying fees in other tokens.
Staking and Bitcoin
Starknet is gradually decentralizing. STRK staking lets holders help secure the network and earn rewards. Since late 2025, Bitcoin can be staked too: STRK makes up 75% of the network’s staking security and BTC 25%, with Bitcoin stakers earning STRK.
In 2026, Starknet launched strkBTC, a version of bitcoin on Starknet with optional privacy features, as part of a push to become a home for “Bitcoin DeFi”.
The STRK token
| STRK at a glance | |
|---|---|
| Total supply | about 10.2 billion STRK (growing slowly) |
| In circulation (Oct 2026) | about 7.6 billion |
| Price (21 Oct 2026) | about $0.056 |
| All-time high | about $4.41 (February 2024) |
| Market cap | about $430 million (#123) |
STRK is used for staking, governance and paying fees. New STRK is created to pay staking rewards, and tokens for the team and early investors have been unlocking monthly since 2024, adding steady selling pressure. STRK’s launch at a very high valuation, followed by years of unlocks, explains much of its fall.
Security and reliability
Starknet’s proofs give strong security, but its sequencer — the system that orders transactions — has been a weak point:
- After the Grinta upgrade in September 2025, which moved from one sequencer to three, the network halted for several hours.
- On 5 January 2026, block production stopped again for roughly two to four hours, depending on the source. No funds were lost.
Full decentralization of sequencing, with every validator able to produce blocks, is planned for 2026.
Money deposited in DeFi apps on Starknet stood at about $160 million in October 2026, according to DeFiLlama, small compared with the leading Layer 2s.
Starknet vs. the competition
| Starknet | Arbitrum | zkSync | |
|---|---|---|---|
| Type | ZK rollup (STARKs) | Optimistic rollup | ZK rollup |
| Withdrawal to Ethereum | Hours | About a week | Hours |
| App language | Cairo | Solidity (and Rust via Stylus) | Solidity |
| Bitcoin staking | Yes | No | No |
Our verdict
Starknet is a technology leader: STARK proofs are among the most advanced tools in crypto, and its smart accounts and Bitcoin staking are genuinely innovative. If ZK rollups become the standard for scaling, Starknet is well positioned.
But adoption hasn’t followed the technology. Usage is small, the network has halted twice in four months, and STRK has lost about 99% of its value since launch amid heavy unlocks. STRK is a very high-risk investment: buy only what you can afford to lose.
This review is for information only and is not financial advice.