Polkadot, launched in 2020 by the Web3 Foundation and Gavin Wood (an Ethereum co-founder), is built around a central relay chain that connects and shares security with a set of independent, specialised blockchains called parachains. Rather than every project bootstrapping its own validator set from scratch, parachains lease security from Polkadot's shared relay chain — an interoperability-first approach distinct from single-chain layer-1s like Solana or Cardano.
Category
layer-1
Consensus mechanism
Proof of Stake (Nominated Proof of Stake)
Launched
2020
Nominated Proof of Stake and parachains
Polkadot's consensus, Nominated Proof of Stake (NPoS), lets DOT holders nominate validators they trust, spreading stake efficiently across the active validator set while limiting how concentrated any one validator's backing can become. Parachains historically won their connection slot through auctions in which projects locked up DOT (their own or contributed by supporters) for a fixed term — a model since supplemented by an on-demand, pay-as-you-go 'coretime' system introduced to lower the barrier for smaller or newer projects.
Governance and use of DOT
DOT is used for staking (securing the relay chain), for parachain bonding, and for on-chain governance, in which token holders vote directly on referenda covering protocol upgrades and treasury spending — a more formalised on-chain governance model than many layer-1s ship with by default.
Tokenomics
| circulating-supply | — |
|---|---|
| max-supply | — |
| issuance-model | No fixed cap; inflationary issuance targets a set validator-staking ratio rather than a total-supply ceiling |
Last verified: 8 July 2026. before you rely on any figure — live circulating supply and market cap are never published here; check a live tracker.
Risks & criticisms
- No fixed maximum supply — DOT issuance targets a validator-staking ratio rather than a hard cap, a materially different monetary model to Bitcoin's or Cardano's.
- The parachain-slot and coretime models have evolved significantly since launch; verify the current mechanism before assuming older auction-based descriptions still apply.
- As an interoperability-focused design, Polkadot's value proposition depends partly on parachain ecosystem growth, which is a different dependency to a self-contained single-chain layer-1.
Where to buy
Related buying guide
→ Polkadot — related buying guideFrequently asked questions
What is a parachain?
An independent, specialised blockchain that connects to Polkadot's central relay chain and shares in its pooled security, rather than needing to bootstrap its own validator set.
Does Polkadot have a maximum DOT supply?
No. There is no hard cap; issuance is inflationary and targets a set proportion of DOT staked, rather than a fixed total.
Who founded Polkadot?
Gavin Wood, a co-founder of Ethereum, founded Polkadot through the Web3 Foundation, launching in 2020.