Polygon (formerly Matic Network) is a blockchain platform which aims to create a multi-chain blockchain system compatible with Ethereum. As with Ethereum, it uses a proof-of-stake consensus mechanism for processing transactions on-chain. Polygon's native token is POL, an ERC-20 token which allows for compatibility with other Ethereum cryptocurrencies. It is operated by Polygon Labs.

Polygon is a natively Layer-2 network that uses Ethereum as a base network. In particular, transactions are first validated inside Polygon and then periodically committed in a "checkpoint": a Merkle root of transaction hashes is committed to Ethereum's mainnet by using "Core contracts".

Polygon runs various decentralized applications (dApps) such as Defi, DAOs, and NFTs.

The blockchain company Polygon was originally known as Matic Network. The Matic Network was launched in 2017 by four software engineers: Jaynti Kanani, Sandeep Nailwal, Anurag Arjun, and Mihailo Bjelic. In February 2021, the project was rebranded as Polygon Technology.

In August 2021, Polygon acquired Hermez Network for $250 million. In December 2021, Polygon acquired the Mir blockchain network for 250 million MATIC tokens, with the tokens having a value of around $400 million at the time of the deal.

In December 2021, Polygon disclosed a security vulnerability that resulted in the theft of 801,601 MATIC tokens.

Polygon employs a modified proof-of-stake consensus technique, which allows consensus to be reached with every block on the blockchain. (Using standard proof-of-stake, achieving consensus will need processing a large number of blocks to establish consensus.) The proof of stake method requires network participants to stake—agree to not trade or sell—their POL tokens, in exchange for the right to validate Polygon network transactions. Successful validators in the Polygon network are rewarded with POL tokens proportionally to their POL stake.

The Polygon network aims to address problems within the Ethereum platform, namely high transaction fees and slow processing speeds.

In January 2024, Polygon announced a new protocol called AggLayer that aims to aggregate zero-knowledge proofs (ZK-proofs) from multiple blockchains and allow developers to connect layer 1 and 2 blockchains to merge them into a single network.

Polygon is the blockchain platform which runs Polymarket, the world's largest prediction market.

In July 2022, Polygon participated in Disney's 2022 acceleration program to expand into augmented reality, NFTs, and AI.

In October 2022, the Indian Police in Firozabad started using Polygon for reporting crimes.