What are Bittensor subnets?

Each subnet has:

• A specific service or task
• Miners who produce the work
• Validators who evaluate it
• Rules for measuring quality and distributing rewards
• Its own subnet number
• Its own Alpha token

The service and scoring method can be very different from one subnet to another.

Technical note+

A subnet’s numerical identifier is called its netuid. Its on-chain participant and performance data is recorded in a metagraph.

A subnet defaults to 256 participant slots, called UIDs, and can be trimmed no lower than 64. Up to 128 UIDs can hold validator permits; the remaining participants can operate as miners. Evaluations and rewards normally settle every 360 blocks, or about 72 minutes.

Subnet owners

Create and maintain the subnet’s purpose, settings and incentive rules.

Miners

Produce the service or result requested by the subnet.

Validators

Evaluate miners’ work and submit scores to the network.

Bittensor combines validator evaluations to determine how rewards are distributed. At each epoch, accumulated Alpha is split 18% to the subnet owner, 41% to miners and 41% to validators with their stakers.

Validator permits are awarded by stake weight and recalculated each epoch. A useful subnet still needs reliable miner output and a scoring method that rewards the intended result.

Subnets have different services and rules, but they all use the shared Subtensor blockchain.

Subtensor coordinates common network activity such as:

• Registration
• Stake
• Validator evaluations
• Rewards
• Shared on-chain records

Each subnet decides what useful work looks like inside its own market.

Subnet space is finite. As reviewed on 5 August 2026, the protocol limit is 128 subnets. When the limit is full, a new registration can deregister the non-immune subnet with the lowest moving Alpha price and reuse its netuid. New subnets are currently protected for 1,296,000 blocks, or about six months.

Creating a subnet requires a dynamic TAO lock. Under the current defaults, the cost doubles after each registration and decays over 100,800 blocks, or about two weeks, towards a 1,000 TAO floor. The lock becomes the subnet’s initial TAO pool reserve rather than a refundable deposit.

Deregistration removes the subnet and all of its UIDs. The subnet’s TAO reserve is then distributed proportionally across Alpha holders, so the final TAO received may differ from the Alpha position’s earlier market value.

TAO

TAO is used across the wider Bittensor network.

It is the asset used to enter and exit positions in service subnets.

Alpha

Each service subnet has its own Alpha token.

Alpha represents a position in that subnet and has its own price, liquidity and reward conditions.

When you stake TAO in a service subnet, your TAO is exchanged for that subnet’s Alpha token. Unstaking exchanges the Alpha back into TAO at the market conditions available at that time.

Root staking is different because the position remains in TAO rather than becoming a subnet Alpha position.

Read “What is TAO?” →

Read “What are Alpha tokens?” →

For these questions applied to live subnets, read the Chutes subnet 64 spotlight and the Lium subnet 51 spotlight.

Start with the service

Start with the service—not the token price or APY.

Ask:

• What does the subnet produce?
• How do validators measure quality?
• Does the incentive system reward the intended result?
• Is the subnet active and understandable?

Then review the position

Then review the position itself:

• Subnet name, number and age
• Alpha liquidity
• Estimated price impact
• Available validators, including their performance and take
• Estimated APY
• Deregistration, technical, market and protocol risks

A higher Alpha price or estimated APY does not prove that one subnet is stronger than another. Both can change quickly.

When you swap TAO into a subnet token, your subnet choice determines:

• The Alpha token you receive
• The market used for the swap
• The available validators
• The estimated rewards shown

Review the subnet name and number before confirming. On supported subnets, your position is also linked to the validator selected in PotaTao.

PotaTao is a non-custodial interface for supported actions. The position and transaction are recorded on the Bittensor network.

Follow “How to swap TAO for a subnet token” →