Bitcoin Halving | Get up to $50 of Bitcoin with a Ledger wallet.

Shop now

Up your Web3 game

Ledger Academy Quests

  • Test your knowledge
  • Earn POK NFTs
Play now See all quests

Nonce Meaning

May 19, 2023 | Updated Jul 19, 2023
A nonce is a variable input used by miners to find a valid hash for a block. It is an authentication model used to verify the validity of data in the blocks.

What is a Cryptographic Nonce?

Nonce is short for ‘number used once’. In blockchain, it is a number added to a hashed block. Miners on a Proof-of-Work (PoW) blockchain have to decode this number before they can earn the right to create the next block. 

In PoW blockchains like Bitcoin, a core component of its security is the “hash”, numbers that are created and validated on the blockchain. Each block in a blockchain has data stored in it, and this data is secured via encryption in the form of “hashed” numbers. These numbers are stored on the block header along with other data, like the nonce.

Miners on the blockchain compete to be the first to decode the nonce. The nonce acts as a variable input during the hashing process, allowing miners to explore a vast space of possibilities to find a valid hash. It serves as a means of adjusting the inputs to the hash function until the desired output is achieved. The PoW algorithm requires miners to continuously search for a nonce value that, when combined with other block data, produces a hash with specific characteristics, such as a certain number of leading zeros.

Miners use nonce to calculate the block hash and then add it to the blockchain. The first miner to successfully find the variable number unlocks the block hash gets block reward and may also receive transaction fees included in the block they mined.

Most blocks are unlocked by mining pools because of the difficulty of finding the right nonce. A single miner’s hashing power may never be sufficient to do this alone, so most miners combine their computing capabilities in order to find the right hash and share the rewards for that block.

Validator

A blockchain validator is a computer or node that verifies transactions in the blockchain network.

Full definition

Depeg

A depeg is a phenomenon that occurs when a stablecoin, which is a cryptocurrency whose value is pegged to another currency, decreases or increases in value relative to the asset it is pegged to.

Full definition

Public Blockchain

A public blockchain is a decentralized network that is not controlled by a single entity. It is accessible to anyone, anywhere in the world.

Full definition