Bitcoin Difficulty & SHA-256 Target Calculator

Block Height:

Block Difficulty:

Network Hashrate:

Block Value:

Mempool Size:

Block Transactions:

Blocks till next Halving:

Mempool Fees (sat/vB)

Low:

Mid:

High:

Previous Block Hash:

Previous Block Difficulty:

Network Target:

Network Difficulty:

Understanding Bitcoin Difficulty

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Difficulty-1 Reference Target (Genesis-Block)

Dec

Hex

How the Target is calculated

Bin

Network Target = Difficulty-1 / Network Difficulty

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Hex

Bitcoin uses a Proof-of-Work system in which SHA-256 hash values are compared with a network-defined target.

For a block to satisfy the Proof-of-Work requirement, its resulting hash must be numerically lower than the current Block Target.

Network Difficulty provides a convenient way to express how restrictive this target is relative to Bitcoin's reference difficulty.

Bitcoin Proof of Work is the process through which computational work is performed and new blocks are proposed to the network.

Let's look at an example. Assume a Difficulty value of 53.94 M.

Bitcoin Difficulty represents a mathematical relationship between a reference target and a corresponding SHA-256 target value.

Dividing the Difficulty-1 reference target by the selected Difficulty produces the corresponding 256-bit target.

The result can then be represented as a 64-digit hexadecimal value.

The calculator below lets you explore this relationship in both directions:

Difficulty → SHA-256 Target or SHA-256 Target → Difficulty

Explore the mathematics behind Bitcoin's Proof-of-Work system and learn how Difficulty, SHA-256 hashes and the network Target are connected.

What is Bitcoin Difficulty?

Bitcoin Difficulty describes how difficult it is for a SHA-256 hash to satisfy the network's current Proof-of-Work requirement.

The Bitcoin network periodically adjusts the Difficulty to keep the average time between blocks close to 10 minutes. As Difficulty increases, the corresponding Target becomes smaller, making the Proof-of-Work requirement more restrictive.

What is the SHA-256 Target?

The Target is a 256-bit threshold defined by the Bitcoin network. A block's SHA-256 hash must be numerically less than or equal to this Target to satisfy the Proof-of-Work requirement.

Because SHA-256 produces 256-bit values, the Target can be represented as a 64-digit hexadecimal number. A smaller Target corresponds to a higher Difficulty.

Why do Bitcoin hashes have leading zeros?

Bitcoin does not explicitly require a specific number of leading zeros. Instead, the resulting SHA-256 hash must be numerically below the current Target.

Because valid Target values are very small compared with the full 256-bit SHA-256 range, qualifying hashes typically begin with multiple zeros when displayed in hexadecimal.

The lower the Target becomes, the more leading zero bits — and usually hexadecimal zeros — appear in hashes that satisfy the requirement.

Difficulty vs. Target

Difficulty and Target have an inverse relationship:

Higher Difficulty → Lower Target

Lower Difficulty → Higher Target

Bitcoin Difficulty is calculated relative to the Difficulty-1 reference Target. Increasing the Difficulty reduces the range of SHA-256 values that can satisfy the network's Proof-of-Work requirement.

This mathematical relationship is the foundation of the Difficulty ↔ Target calculations available on BTCMCalc.