Lower limit on burn registration cost.
Current Value
0.0005 TAO (500000 raw)
Conversion: ÷ 10^9 (RAO → TAO)
Relevant for: minersvalidatorssubnet ownersdevelopers
The Big Picture
Even when a subnet has low demand, burn cost won't drop below this floor. This ensures some economic cost always exists for burn registration, preventing spam and ensuring registrants have skin in the game. The minimum provides price stability for low-traffic subnets.
Why This Matters
This is your best-case scenario for burn registration cost. On quiet subnets, burn settles to this minimum, making registration cheap.
Example
With MinBurn of 0.1 TAO, even an idle subnet requires 0.1 TAO to burn-register. This tiny amount discourages spam while keeping registration accessible.
Common Questions
- Why not allow free burn registration?
- Free registration enables Sybil attacks - creating thousands of identities at no cost. Even a tiny burn ensures economic commitment.
- Can I get emissions back to cover burn cost?
- Yes, if you perform well. Good miners/validators earn emissions that can exceed registration cost. But burned TAO itself is gone forever.
From Chain Metadata
Initial Min Burn.
Use Cases
- Burn registration
- Cost limits
Value History
| Version | Block | Change | Value |
|---|---|---|---|
| v101 | #1 | Added | 1.00 TAO |
| v233 | #4,920,350 | Changed | 1.00 TAO → 0.0005 TAO |
Code Examples
import { ApiPromise, WsProvider } from "@polkadot/api";
import { stringCamelCase } from "@polkadot/util";
const provider = new WsProvider("wss://entrypoint-finney.opentensor.ai:443");
const api = await ApiPromise.create({ provider });
// Query InitialMinBurn constant
const value = api.consts[stringCamelCase("SubtensorModule")][stringCamelCase("InitialMinBurn")];
console.log("InitialMinBurn:", value.toHuman());
// Convert RAO to TAO if this is a balance value
const taoValue = value.toBigInt() / BigInt(1e9);
console.log("TAO:", taoValue.toString());Type Information
- Type
- u64
- Byte Size
- 8 bytes
- Encoding
- fixed
- Raw Hex
- 0x20a1070000000000
Version History
v101 block 1 Added
v233 block 4,920,350 Re-added Current
Runtime Info
- Pallet
- SubtensorModule
- First Version
- v101
- Latest Version
- v101
- Current Runtime
- v393