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A compressed account is a Solana account whose state is stored as a leaf in an on-chain Concurrent Merkle Tree rather than as a dedicated on-chain account, making it 100–1,000x cheaper to create and maintain because no rent-exempt lamport balance is required per account. Compressed accounts are identified by a hash of their data and position in the tree; to interact with one, a client must supply a Merkle proof (or rely on the canopy) showing the leaf is part of the current tree root, which the on-chain program verifies before processing the state change. Light Protocol's compressed account model supports arbitrary data, discriminators, and owner programs, making it a general-purpose replacement for expensive on-chain accounts in high-volume use cases.

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Compressed state, proofs, and scale-oriented storage patterns.

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Compressed Account (compressed-account)
Category: ZK Compression
Definition: A compressed account is a Solana account whose state is stored as a leaf in an on-chain Concurrent Merkle Tree rather than as a dedicated on-chain account, making it 100–1,000x cheaper to create and maintain because no rent-exempt lamport balance is required per account. Compressed accounts are identified by a hash of their data and position in the tree; to interact with one, a client must supply a Merkle proof (or rely on the canopy) showing the leaf is part of the current tree root, which the on-chain program verifies before processing the state change. Light Protocol's compressed account model supports arbitrary data, discriminators, and owner programs, making it a general-purpose replacement for expensive on-chain accounts in high-volume use cases.
Related: ZK Compression, State Compression

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ZK Compression

ZK Compression, pioneered by Light Protocol, extends Solana's state compression model beyond NFTs to general-purpose compressed accounts by using zero-knowledge proofs (specifically Groth16 SNARKs verified via the alt_bn128 syscall) to prove the validity of state transitions without storing full account state on-chain. Compressed accounts live in on-chain Merkle trees but their data is reconstructed from the Solana ledger by indexers like Photon, enabling developers to build applications that use thousands of accounts at a fraction of the normal rent cost — often 1,000x to 5,000x cheaper than regular accounts. The protocol introduces compressed tokens, compressed PDAs, and a system of nullifiers to prevent double-spends while maintaining Solana's throughput.

Open term

Branch

State Compression

State Compression is Solana's technique for storing the cryptographic fingerprint (root hash) of a Merkle tree on-chain while keeping the actual leaf data off-chain in the Solana ledger's account data logs, reducing the cost of storing large datasets by orders of magnitude. A compressed NFT collection of 1 million items costs roughly 50 SOL to mint versus ~12,000 SOL with standard SPL accounts, because only a single Concurrent Merkle Tree account occupies on-chain storage. Any data change requires updating the root hash and supplying a Merkle proof to the on-chain program, which verifies inclusion without reading the full dataset.

Concurrent Merkle Tree Compressed NFT (cNFT)

Open term

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ZK Compression

ZK Compression, pioneered by Light Protocol, extends Solana's state compression model beyond NFTs to general-purpose compressed accounts by using zero-knowledge proofs (specifically Groth16 SNARKs verified via the alt_bn128 syscall) to prove the validity of state transitions without storing full account state on-chain. Compressed accounts live in on-chain Merkle trees but their data is reconstructed from the Solana ledger by indexers like Photon, enabling developers to build applications that use thousands of accounts at a fraction of the normal rent cost — often 1,000x to 5,000x cheaper than regular accounts. The protocol introduces compressed tokens, compressed PDAs, and a system of nullifiers to prevent double-spends while maintaining Solana's throughput.

Open term

ZK Compression

State Compression

State Compression is Solana's technique for storing the cryptographic fingerprint (root hash) of a Merkle tree on-chain while keeping the actual leaf data off-chain in the Solana ledger's account data logs, reducing the cost of storing large datasets by orders of magnitude. A compressed NFT collection of 1 million items costs roughly 50 SOL to mint versus ~12,000 SOL with standard SPL accounts, because only a single Concurrent Merkle Tree account occupies on-chain storage. Any data change requires updating the root hash and supplying a Merkle proof to the on-chain program, which verifies inclusion without reading the full dataset.

Open term

ZK Compression

Compressed PDA

A PDA-like addressing scheme for compressed accounts in the ZK Compression system. Compressed PDAs provide deterministic, program-derived addressing for compressed account leaves, enabling programs to locate and reference compressed state using seeds and program IDs similar to regular PDAs. The address is derived from seeds and stored as part of the compressed account's leaf data in the Merkle tree, with the Light System Program enforcing uniqueness through an address queue and nullifier mechanism.

Open term

ZK Compression

Canopy Depth

The number of top levels of a Concurrent Merkle Tree that are cached on-chain within the CMT account, reducing the Merkle proof size that clients must include in transactions. A canopy depth of D means the top D levels (2^D - 1 nodes) are stored on-chain, so clients only need to supply (tree_depth - D) sibling hashes instead of the full tree_depth. Deeper canopies reduce transaction size and compute costs but increase the CMT account's rent-exempt balance. Choosing optimal canopy depth is a cost trade-off between on-chain storage rent and per-transaction proof overhead.

Open term

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ZK Compressioncompressed-pda

Compressed PDA

A PDA-like addressing scheme for compressed accounts in the ZK Compression system. Compressed PDAs provide deterministic, program-derived addressing for compressed account leaves, enabling programs to locate and reference compressed state using seeds and program IDs similar to regular PDAs. The address is derived from seeds and stored as part of the compressed account's leaf data in the Merkle tree, with the Light System Program enforcing uniqueness through an address queue and nullifier mechanism.

Open term

ZK Compressioncompressed-token

Compressed Token

A compressed token is an SPL-compatible fungible or semi-fungible token whose per-account token balances are stored as leaves in a Concurrent Merkle Tree via Light Protocol's Compressed Token Program rather than as individual Token or Token-2022 accounts, reducing the account creation cost from ~0.002 SOL per token account to a negligible fraction of a lamport per leaf. Compressed tokens implement the same mint, transfer, burn, and delegation semantics as standard SPL tokens, but every operation requires a Merkle proof of the source leaf's existence and a validity proof of the state transition; the Compressed Token Program wraps the Light System Program to handle this ZK machinery transparently. This design is particularly valuable for airdrops, gaming economies, and reward systems where millions of user token accounts would otherwise impose prohibitive rent costs on the issuer or recipient.

Open term

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ZK Compressionzk-compression

ZK Compression

ZK Compression, pioneered by Light Protocol, extends Solana's state compression model beyond NFTs to general-purpose compressed accounts by using zero-knowledge proofs (specifically Groth16 SNARKs verified via the alt_bn128 syscall) to prove the validity of state transitions without storing full account state on-chain. Compressed accounts live in on-chain Merkle trees but their data is reconstructed from the Solana ledger by indexers like Photon, enabling developers to build applications that use thousands of accounts at a fraction of the normal rent cost — often 1,000x to 5,000x cheaper than regular accounts. The protocol introduces compressed tokens, compressed PDAs, and a system of nullifiers to prevent double-spends while maintaining Solana's throughput.

Open term

ZK Compressionstate-compression

State Compression

State Compression is Solana's technique for storing the cryptographic fingerprint (root hash) of a Merkle tree on-chain while keeping the actual leaf data off-chain in the Solana ledger's account data logs, reducing the cost of storing large datasets by orders of magnitude. A compressed NFT collection of 1 million items costs roughly 50 SOL to mint versus ~12,000 SOL with standard SPL accounts, because only a single Concurrent Merkle Tree account occupies on-chain storage. Any data change requires updating the root hash and supplying a Merkle proof to the on-chain program, which verifies inclusion without reading the full dataset.

Open term

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ZK Compression

State Compression

State Compression is Solana's technique for storing the cryptographic fingerprint (root hash) of a Merkle tree on-chain while keeping the actual leaf data off-chain in the Solana ledger's account data logs, reducing the cost of storing large datasets by orders of magnitude. A compressed NFT collection of 1 million items costs roughly 50 SOL to mint versus ~12,000 SOL with standard SPL accounts, because only a single Concurrent Merkle Tree account occupies on-chain storage. Any data change requires updating the root hash and supplying a Merkle proof to the on-chain program, which verifies inclusion without reading the full dataset.

Open term

ZK Compression

ZK Compression, pioneered by Light Protocol, extends Solana's state compression model beyond NFTs to general-purpose compressed accounts by using zero-knowledge proofs (specifically Groth16 SNARKs verified via the alt_bn128 syscall) to prove the validity of state transitions without storing full account state on-chain. Compressed accounts live in on-chain Merkle trees but their data is reconstructed from the Solana ledger by indexers like Photon, enabling developers to build applications that use thousands of accounts at a fraction of the normal rent cost — often 1,000x to 5,000x cheaper than regular accounts. The protocol introduces compressed tokens, compressed PDAs, and a system of nullifiers to prevent double-spends while maintaining Solana's throughput.

Open term

ZK Compression

Concurrent Merkle Tree

A Concurrent Merkle Tree (CMT) is a specialized on-chain Solana data structure that allows multiple state updates to the same Merkle tree within a single block without conflicting, by recording a changelog buffer of recent root transitions that validators use to reconcile parallel proof submissions. A CMT is parameterized by its maximum depth (max_depth, determining tree capacity of 2^max_depth leaves), max_buffer_size (number of concurrent changes the changelog can track, directly controlling how many operations per slot the tree can safely absorb), and an optional canopy_depth. The SPL Account Compression program manages CMTs, and they are the foundational storage primitive for both Metaplex compressed NFTs and Light Protocol compressed accounts.

Open term

ZK Compression

Merkle Proof

A Merkle proof is the minimal set of sibling node hashes (the proof path) along the branch from a specific leaf to the tree root, allowing anyone to independently verify that a given leaf is part of a Merkle tree by recomputing the root from the leaf hash and the sibling hashes without needing any other tree data. In Solana's state compression, every compressed account or compressed NFT interaction requires the caller to supply a valid Merkle proof; the on-chain program hashes the proof against the current root stored in the Concurrent Merkle Tree account to confirm inclusion before executing the state change. Proof size scales linearly with tree depth (e.g., a depth-20 tree requires up to 20 sibling hashes, each 32 bytes), so the canopy is used to pre-store upper-level nodes on-chain to reduce the proof data that must be passed in transactions.

Open term