DepositPerByte

Constant v334 → current u64

Economic mechanism to prevent unbounded state growth.

Current Value

0.00000003 TAO (30 raw)

Conversion: ÷ 10^9 (RAO → TAO)

Relevant for: developers

The Big Picture

Storage isn't free. Every byte of code or contract storage requires a deposit. This constant sets the rate: total_deposit = bytes * DepositPerByte. Larger contracts cost more to deploy.

From Chain Metadata

The amount of balance a caller has to pay for each byte of storage. # Note Changing this value for an existing chain might need a storage migration.

Use Cases

  • Calculate storage costs for contracts
  • Estimate deployment deposits
  • Plan contract economics

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 DepositPerByte constant
const value = api.consts[stringCamelCase("Contracts")][stringCamelCase("DepositPerByte")];
console.log("DepositPerByte:", 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
0x1e00000000000000

Runtime Info

Pallet
Contracts
First Version
v334
Latest Version
v334
Current Runtime
v393