What Is Chainlink (LINK)?

Blockchains cannot see anything outside their own network. A smart contract on Ethereum cannot check the price of gold or the score of a match by itself. Chainlink was built to fill that gap.

Its token, LINK, is an altcoin, meaning any cryptocurrency other than Bitcoin. To see how it fits into the wider group, read our guide to what altcoins are.

This guide does not quote prices, because they change all the time. See the Chainlink price and payment options for the current LINK rate.

What is Chainlink?

Chainlink is a decentralized oracle network. It is a network of independent nodes that fetch information from outside a blockchain and deliver it to smart contracts, so those contracts can react to real-world events.

Blockchains are closed on purpose: every node must reach the same result from the same on-chain data, so a smart contract cannot look up a market price on its own. A service that brings in that data is called an oracle. An oracle run by one company is a single point of failure, so Chainlink spreads the work across many independent node operators and data sources.

Price data feeds were Chainlink’s first service. Lending apps use them to value the collateral behind loans; Aave, for example, lists Chainlink price feeds among its main oracle types. Chainlink also offers Proof of Reserve (checks that a token is backed by the assets it claims), VRF (random numbers that can be verified, used in games and NFT draws) and Automation (runs a contract’s functions when set conditions are met). Many decentralized finance (DeFi) apps rely on these services.

How do Chainlink oracles work?

Independent nodes each fetch the same data, their answers are combined into one value, and that value is written to the blockchain. The 2017 whitepaper named three steps: oracle selection, data reporting and result aggregation. Today’s price feeds work like this:

A feed updates when the price moves by more than a set amount (the deviation threshold) or when a set time has passed (the heartbeat). Because many nodes feed each answer, no single node can set the price. If too few nodes respond, the feed does not update, so apps need to check how fresh the data is.

What is LINK used for?

LINK pays for Chainlink’s services and helps secure the network. It has three main uses:

• Paying for services. Node operators earn LINK for delivering data and other services. Chainlink says users can also pay service fees in other assets or regular money, which are then converted into LINK.
• Staking. Holders can lock up LINK to back the performance of Chainlink’s services. Staking v0.2, live since November 2023, is capped at 45 million LINK and at launch secured the ETH/USD feed on Ethereum. Node operators can be slashed (lose part of their stake) if a valid alert shows the feed is not working as it should; community stakers are not slashed in v0.2.
• The Chainlink Reserve. Since August 2025, Chainlink has converted part of its revenue into LINK and kept it in an on-chain reserve. It says it does not expect any withdrawals for multiple years.

LINK is an ERC-677 token on Ethereum. ERC-677 builds on the common ERC-20 token standard and lets a transfer carry extra data, so LINK can be sent to a contract and used in one step. Official LINK token contracts also exist on other blockchains, and Chainlink lists them in its documentation. The total supply is capped at 1 billion LINK.

What is CCIP?

CCIP, short for Cross-Chain Interoperability Protocol, is Chainlink’s system for sending messages and tokens between different blockchains. An app on one chain can send instructions, tokens, or both at once to an app on another chain.

Blockchains cannot read each other’s data, so moving value between them needs a bridge. Bridges have been a major target for hackers. Chainalysis found that $3.1 billion was stolen from DeFi apps in 2022, and 64% of that came from cross-chain bridges.

CCIP entered early access in July 2023 on Avalanche, Ethereum, Optimism and Polygon, and became generally available in April 2024. On September 28, 2026, Chainlink launched CCIP 2.0. Transfers are checked by a default committee of 16 independent node operators, and token issuers can now add verifiers of their own on top. Like any cross-chain system, CCIP still carries risk.

What is the history of Chainlink?

Chainlink began with a whitepaper by Steve Ellis, Ari Juels and Sergey Nazarov, published on September 4, 2017. Its main network went live in May 2019.

The token sale was an initial coin offering (ICO). According to Cointelegraph, it raised $32 million by selling 35% of the 1 billion LINK. Another 35% was set aside to reward node operators, and 30% went to the company developing Chainlink.

What are the risks of Chainlink?

The main risks are bad data, a concentrated token supply, staking lock-ups, price swings and scams.

• Oracle failures. If a feed reports a wrong price or stops updating, apps that rely on it can liquidate loans unfairly or lose funds. Chainlink’s documentation makes developers responsible for their own data checks and safety switches.
• Price manipulation. Attackers try to distort the prices oracles report. Chainalysis counted 41 oracle manipulation attacks on DeFi apps in 2022, across many kinds of oracles, with $403.2 million lost.
• Token concentration. Only 35% of LINK was sold in the 2017 token sale. The rest was kept for node-operator rewards and the company, so a large share of the supply started out in the hands of a few parties.
• Staking lock-ups. Unstaking LINK takes a 28-day cooldown, followed by a 7-day window to claim it.
• Volatility. LINK’s price can swing sharply, and no company or government stands behind its value. Learn what volatility is.
• Scams. Fake staking and airdrop sites ask you to connect your wallet or share your recovery phrase. The US Federal Trade Commission (FTC) warns that only scammers promise sure profits or big returns.

Learn the warning signs in common scams in the crypto industry and how to protect yourself from fraud.

How can I buy LINK?

You can buy LINK through a crypto exchange or broker that offers it and keep it in a wallet you control. Set up the wallet first, because you will need its address.

See the Chainlink price and payment options before you decide.

Robi Uzan

All Posts »