> ## Documentation Index > Fetch the complete documentation index at: https://docs.starknet.io/llms.txt > Use this file to discover all available pages before exploring further. # Chain information You can get the latest updates delivered to your inbox by subscribing to the [Starknet Devs Newsletter](https://www.starknet.io/starknet-devs-newsletter/). ## Current versions | Environment | Starknet version | Sierra version | Cairo version | | ----------- | ---------------- | -------------- | -------------- | | Mainnet | 0.14.2 | 1.7.0 | 2.0.0 - 2.18.0 | | Sepolia | 0.14.2 | 1.7.0 | 2.0.0 - 2.18.0 | ## Current limits The following limits are subject to revisions and change on a regular basis 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. | 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

**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

**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

**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

**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 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). | 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 A deprecated feature is a feature that is still supported, but support will be removed in a future release of Starknet. | 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).

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 An unsupported feature is a feature that is no longer supported. A removed feature is a feature that has been entirely removed. | 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.

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).

Full nodes, API services, SDKs, and other Starknet developer tools have migrated to Sepolia as well.

**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).

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:

**Environment** \| **Date**
Integration \| 1 November 2023
Testnet \| 15 November 2023
Mainnet \| 19 December 2023

Queries that are required for full nodes to synchronize on the state of Starknet are still supported.

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.

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.

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).

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 |