Many of these parameter values can be updated via on-chain governance. If you require absolute certainty of these parameter values, it is recommended you directly check the constants by looking at the chain state and/or storage.
Periods of common actions and attributes
NOTE: Polkadot generally runs at ¼th the speed of Kusama, except in the time slot duration itself. See Kusama Parameters for more details on how Polkadot's parameters differ from Kusama's.
- Slot: 6 seconds *(generally one block per slot, although see note below)
- Epoch: 4 hours (2_400 slots x 6 seconds)
- Session: 4 hours (Session and Epoch lengths are the same)
- Era: 24 hours (6 sessions per Era, 2_400 slots x 6 epochs x 6 seconds)
*A maximum of one block per slot can be in a canonical chain. Occasionally, a slot will be without a block in the chain. Thus, the times given are estimates. See Consensus for more details.
Accounts, Identity and Crowdloans
- The Existential Deposit is
- The deposit required to set an Identity is
- The minimum contribution required to participate in a crowdloan is
|Voting period||28 days||403_200||How long the public can vote on a referendum.|
|Launch period||28 days||403_200||How long the public can select which proposal to hold a referendum on, i.e., every week, the highest-weighted proposal will be selected to have a referendum.|
|Enactment period||28 days||403_200||Time it takes for a successful referendum to be implemented on the network.|
|Term duration||7 days||100_800||The length of a council member's term until the next election round.|
|Voting period||7 days||100_800||The council's voting period for motions.|
The Polkadot Council consists of up to 13 members and up to 20 runners up.
|Cool-off period||7 days||100_800||The time a veto from the technical committee lasts before the proposal can be submitted again.|
|Emergency voting period||3 hours||1_800||The voting period after the technical committee expedites voting.|
Staking, Validating, and Nominating
The maximum number of validators that can be nominated by a nominator is .
|Term duration||1 Day||14_400||The time for which a validator is in the set after being elected. Note, this duration can be shortened in the case that a validator misbehaves.|
|Nomination period||1 Day||14_400||How often a new validator set is elected according to Phragmén's method.|
|Bonding duration||28 days||403_200||How long until your funds will be transferrable after unbonding. Note that the bonding duration is defined in eras, not directly by slots.|
|Slash defer duration||28 days||403_200||Prevents overslashing and validators "escaping" and getting their nominators slashed with no repercussions to themselves. Note that the bonding duration is defined in eras, not directly by slots.|
|Crowdloans and Auctions||Time||Slots||Description|
|Auction duration||7 days||100_800||The total duration of the slot auction, subject to the candle auction mechanism.|
|Opening period||2 days||28_800||The opening period of the slot auction.|
|Ending period||5 days||72_000||The ending period of the slot auction.|
|Lease period||12 weeks||1_209_600||The length of one lease period in a parachain slot.|
|Total slot duration||2 years||10_512_000||The maximum duration a parachain can lease by winning a slot auction (8 lease periods).|
|Periods between spends||24 days||345_600||When the treasury can spend again after spending previously.|
Burn percentage is currently
DOT have 10 decimals of precision. In other words, 10 ** 10 (10_000_000_000 or ten billion) Plancks make up a DOT.
The denomination of DOT was changed from 12 decimals of precision at block #1,248,328 in an event known as Denomination Day. See Redenomination for details.