Polkadot does not have a maximum supply . DOT is inflationary. You can read more about that here. There are currently just over 1 billion DOT in issuance.
Read moreDoes Polkadot have a coin?
The Polkadot token (DOT) serves two main functions within the Polkadot network: it’s a governance token, which allows holders to have a say in the future of the protocol, and it’s used for staking, which is the way the Polkadot network verifies transactions and issues new DOT.
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