> ## Documentation Index
> Fetch the complete documentation index at: https://starkware-9575960b-starkzapv4.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Chain information

<Tip>
  You can get the latest updates delivered to your inbox by subscribing to the [Starknet Devs Newsletter](https://www.starknet.io/starknet-devs-newsletter/).
</Tip>

## Current versions

| Environment | Starknet version | Sierra version | Cairo version |
| - | - | - | - |
| Mainnet | 0.14.2 | 1.7.0 | 2.0.0 - 2.18.0 |
| Sepolia | 0.14.3 | 1.9.0 | 2.0.0 - 2.19.0 |

## Current limits (mainnet)

<Warning>
  The following limits are subject to revisions and change on a regular basis
</Warning>

<Note>
  Starting from v0.13.0, blockifier-related constants and limits are defined for each Starknet version in a JSON file called `versioned_constants` in the [blockifier's resources directory](https://github.com/starkware-libs/sequencer/tree/main/crates/blockifier/resources).

  Starting from v0.13.5, resources are denominated in units of L2 gas, L1 gas, and L1 data gas.
</Note>

| Entity | Description | Limit |
| - | - | - |
| Block time | The maximum amount of time within which a preconfirmed block is closed, if no other limit is met | 9.5 seconds |
| Block recommended time | The amount of time after which preconfirmed block is closed, if there are no transactions in the mempool and no transactions being executed ATM | 2 seconds |
| Max L2 gas per block | The maximum amount of L2 gas that a block can contain<br /><br />**Note:** This limit ensures block production times remains consistent and predictable. | 6 \* 10^9 |
| Max transactions per block | The maximum amount of transactions in a single block | 500 |
| Max L2 gas per transaction | The maximum number of computational steps, measured in L2 gas, that a transaction can contain when processed on the Starknet network<br /><br />**Note:** This limit is important for ensuring the efficient execution of transactions and preventing potential congestion. | 1.1\*10^9 |
| Max state updates per transaction | The maximum number of storage updates that a single transaction can generate<br /><br />**Note:** This limit helps maintain network stability and predictable performance. | 2,490 |
| Max number of events per transaction | The maximum number of events that a transaction can emit during its execution | 1,000 |
| Max number of data felts per event | The maximum number of felts that an event can contain in its `data` array | 300 |
| Max number of key felts per event | The maximum number of felts that an event can contain in its `keys` array | 50 |
| Max L2 gas for `validate` | The maximum number of computational steps, measured in Cairo steps, for a `validate` function | 10^8 |
| Max contract bytecode size | The maximum size of the bytecode or program that a smart contract can have on Starknet | 81,920 felts |
| Max contract class size | The maximum size for the Sierra file of a contract class within Starknet<br /><br />**Note:** This limit is important for ensuring the network's scalability and security. | 4,089,446 bytes |
| IP address limits | The amount of contract reads that a single IP address can make (in order to reduce network spam) | 200 per min per IP address |
| Signature length | The maximum length of a signature | 4,000 felts |
| Calldata length | The maximum length of a transaction calldata | 5,000 felts |

### Block builtin limits

<Warning>
  Currently, block builtin limits apply only for Sepolia.

  For more information, see [the release notes for Starknet version 0.13.6](/learn/cheatsheets/version-notes#starknet_v0_13_6_8_jul_25).
</Warning>

| Builtin | Limit |
| - | - |
| Range Check | 57,142,857 |
| ECDSA | 3,000 |
| Poseidon | 479,961 |
| Pedersen | 493,827 |
| Bitwise | 6,861,063 |
| EC OP | 6,994 |
| Keccak | 9,790 |
| Range Check 96 | 71,428,571 |
| Add Mod | 16,000,000 |
| Mul Mod | 6,622,516 |

## Deprecated features

<Note>
  A deprecated feature is a feature that is still supported, but support will be removed in a future release of Starknet.
</Note>

| Name | Description |
| - | - |
| Cairo 0 | [Starknet v0.11.0](/learn/cheatsheets/version-notes#version0.11.0) introduces Cairo 1.0 smart contracts. |
| Transaction signing only over two resources | RPC version 0.8, introduced in Starknet 0.13.5, only supports `v3` transactions that sign over three resources (L1 gas, L2 gas and L1 data gas), removing support for transaction versions `v0`, `v1`, and `v2`, and for `v3` transactions that sign only over two resources (L1 gas and L2 gas).<br /><br />Starting from version v0.14.0, Starknet will stop accepting these transactions altogether, and will only accept `v3` transactions compliant with RPC 0.8. |

## Unsupported and removed features

<Note>
  An unsupported feature is a feature that is no longer supported.

  A removed feature is a feature that has been entirely removed.
</Note>

| Name | Description |
| - | - |
| Starknet CLI | Support for the Starknet CLI has been removed. Instead use [`Starkli or Starknet Foundry's sncast`](./tools). |
| Goerli testnet | Goerli testnet support was removed April 2, 2024. Sepolia testnet replaces Goerli testnet.<br /><br />Starknet started migrating to Sepolia testnet on November 15th, 2023. For more information on the Goerli deprecation, see [the deprecation announcement on Ethereum's site](https://ethereum.org/nb/developers/docs/networks/#ethereum-testnets).<br /><br />Full nodes, API services, SDKs, and other Starknet developer tools have migrated to Sepolia as well.<br /><br />**Note:** Sepolia's state and history are relatively small. Sepolia [supports declaring classes of CairoZero and Cairo v2.0.0 and higher](/learn/cheatsheets/version-notes). |
| Starknet feeder gateway | The Starknet feeder gateway, a temporary solution for querying the sequencer's state, is being replaced by Starknet full nodes (Pathfinder, Juno, Deoxys, Papyrus) and RPC services. For more information, see [Full nodes and API services](./tools).<br /><br />Support for the feeder gateway queries that are not required for full nodes to synchronize on the state of Starknet will stop according to the following schedule:<br /><br />**Environment** \| **Date**<br />Integration \| 1 November 2023<br />Testnet \| 15 November 2023<br />Mainnet \| 19 December 2023<br /><br />Queries that are required for full nodes to synchronize on the state of Starknet are still supported.<br /><br />For more information, see the Community Forum post [*Feeder Gateway Deprecation*](https://community.starknet.io/t/feeder-gateway-deprecation/100233). |
| Free L1-> L2 messaging | Previously, sending a message from L1 to L2 had an optional fee associated.<br /><br />From [Starknet v0.11.0](/learn/cheatsheets/version-notes#version0.11.0), the fee mechanism is enforced and the ability to send L1->L2 messages without the corresponding L2 fee has been removed.<br /><br />See [here](/learn/protocol/messaging#l1-l2-message-fees) for more details. |
| `invoke` transaction v0 | `invoke` transaction v0 has been removed since [Starknet v0.11.0](/learn/cheatsheets/version-notes#version0.11.0). |
| `declare` transaction v0 | `declare` transaction v0 has been removed since [Starknet v0.11.0](/learn/cheatsheets/version-notes#version0.11.0). |
| `deploy` transaction | The `deploy` transaction has been removed since [Starknet v0.10.3](/learn/cheatsheets/version-notes#version0.10.3).<br /><br />To deploy new contract instances, you can use the [`deploy system call`](https://book.cairo-lang.org/appendix-08-system-calls.html#deploy). |

## Important addresses

### General

#### Mainnet

| | |
| - | - |
| Sequencer base URL | alpha-mainnet.starknet.io |
| Core contract | 0xc662c410C0ECf747543f5bA90660f6ABeBD9C8c4 |
| SHARP verifier contract | 0x47312450B3Ac8b5b8e247a6bB6d523e7605bDb60 |

#### Sepolia

| | |
| - | - |
| Sequencer base URL | alpha-sepolia.starknet.io |
| Core contract | 0xE2Bb56ee936fd6433DC0F6e7e3b8365C906AA057 |
| SHARP verifier contract | 0x07ec0D28e50322Eb0C159B9090ecF3aeA8346DFe |

### Tokens

#### Mainnet

| | |
| - | - |
| STRK contract | 0x04718f5a0fc34cc1af16a1cdee98ffb20c31f5cd61d6ab07201858f4287c938d |
| ETH contract | 0x049d36570d4e46f48e99674bd3fcc84644ddd6b96f7c741b1562b82f9e004dc7 |
| vSTRK contract | 0x0782f0ddca11d9950bc3220e35ac82cf868778edb67a5e58b39838544bc4cd0f |

#### Sepolia

| | |
| - | - |
| STRK contract | 0x04718f5a0fc34cc1af16a1cdee98ffb20c31f5cd61d6ab07201858f4287c938d |
| ETH contract | 0x049d36570d4e46f48e99674bd3fcc84644ddd6b96f7c741b1562b82f9e004dc7 |
| vSTRK contract | 0x035c332b8de00874e702b4831c84b22281fb3246f714475496d74e644f35d492 |

### StarkGate

#### Mainnet

| | |
| - | - |
| StarkgateManager contract | 0x0c5aE94f8939182F2D06097025324D1E537d5B60 |
| StarkgateRegistry contract | 0x1268cc171c54F2000402DfF20E93E60DF4c96812 |
| L1 StarknetTokenBridge contract | 0xF5b6Ee2CAEb6769659f6C091D209DfdCaF3F69Eb |
| L2 StarknetTokenBridge contract | 0x0616757a151c21f9be8775098d591c2807316d992bbc3bb1a5c1821630589256 |
| Bridged tokens | [https://github.com/starknet-io/starknet-addresses/blob/master/bridged\_tokens/mainnet.json](https://github.com/starknet-io/starknet-addresses/blob/master/bridged_tokens/mainnet.json) |

#### Sepolia

| | |
| - | - |
| Bridged tokens | [https://github.com/starknet-io/starknet-addresses/blob/master/bridged\_tokens/sepolia.json](https://github.com/starknet-io/starknet-addresses/blob/master/bridged_tokens/sepolia.json) |

### Staking

#### Mainnet

| | |
| - | - |
| Staking contract | 0x00ca1702e64c81d9a07b86bd2c540188d92a2c73cf5cc0e508d949015e7e84a7 |
| L1 Reward supplier contract | 0xCa1406D57eD09947E68DE121316C87113fBE9ff5 |
| L2 Reward supplier contract | 0x009035556d1ee136e7722ae4e78f92828553a45eed3bc9b2aba90788ec2ca112 |
| Mint manager contract | 0xCa14076A3cec95448BaD179cc19B351A4204B88B |
| Minting curve contract | 0x00ca1705e74233131dbcdee7f1b8d2926bf262168c7df339004b3f46015b6984 |
| Attestation contract | 0x10398fe631af9ab2311840432d507bf7ef4b959ae967f1507928f5afe888a99 |

| **Stakable tokens** | |
| :- | :- |
| STRK | 0x04718f5a0fc34cc1af16a1cdee98ffb20c31f5cd61d6ab07201858f4287c938d |
| WBTC | 0x03fe2b97c1fd336e750087d68b9b867997fd64a2661ff3ca5a7c771641e8e7ac |
| SolvBTC | 0x0593e034dda23eea82d2ba9a30960ed42cf4a01502cc2351dc9b9881f9931a68 |
| tBTC | 0x04daa17763b286d1e59b97c283c0b8c949994c361e426a28f743c67bdfe9a32f |
| LBTC | 0x036834a40984312f7f7de8d31e3f6305b325389eaeea5b1c0664b2fb936461a4 |

#### Sepolia

| | |
| - | - |
| Staking contract | 0x03745ab04a431fc02871a139be6b93d9260b0ff3e779ad9c8b377183b23109f1 |
| L1 Reward supplier contract | 0xE58d25681B9d290D60e4d7f379a05d5BFD973fFB |
| L2 Reward supplier contract | 0x02ebbebb8ceb2e07f30a5088f5849afd4f908f04f3f9c97c694e5d83d2a7cc61 |
| Mint manager contract | 0x648D1B35a932F5189e7ff97b2F795E03734DE4ce |
| Minting curve contract | 0x06043928ca93cff6d6f39378ba391d7152eea707bdd624c1b2074e71af2abaca |
| Attestation contract | 0x03f32e152b9637c31bfcf73e434f78591067a01ba070505ff6ee195642c9acfb |

| **Stakable tokens** | |
| :- | :- |
| STRK | 0x04718f5a0fc34cc1af16a1cdee98ffb20c31f5cd61d6ab07201858f4287c938d |
| TestBTC1 token | 0x044ad07751ad782288413c7db42c48e1c4f6195876bca3b6caef449bb4fb8d36 |
| TestBTC2 token | 0x07e97477601e5606359303cf50c050fd3ba94f66bd041f4ed504673ba2b81696 |


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