Hey there! I have been for a long time in dApps developement and I know on my own how it is difficult to get started with blockchain APIs. Especially with their endpoints. I decided to gather the most important endpoints for Ethereum, Binance, Bitcoin, Ploygon, and Solana blockchains in this article.

I tried to be consistent and to the point. Hope they will help you!

Ethereum API

The Ethereum API is fundamental for developers working on the Ethereum network. It provides access to blockchain data, enabling interaction with smart contracts and account management. Key endpoints include:

1. eth_call. Executes a message call immediately without creating a transaction.
2. eth_getTransactionByHash. Retrieves transaction details using its hash.
3. eth_getBlockByNumber. Returns block information by its number.
4. eth_getCode. Retrieves the code at a specific address, useful for checking smart contracts' bytecode.
5. eth_getLogs. Fetches logs from smart contracts, often used to track events like token transfers.
6. eth_estimateGas. Estimates the gas required to execute a transaction, helping developers calculate costs.
7. eth_gasPrice. Returns the current gas price in the network, essential for setting transaction fees.
8. eth_getTransactionCount. Retrieves the number of transactions sent from an address, often used to get the nonce for new transactions.

These endpoints are imperative for building dApps that require real-time blockchain data. I mean DeFi platforms and NFT marketplaces. For example, eth_call is used to query token balances in smart contracts without broadcasting a transaction.

Solana API

Solana's API is designed for high-speed, scalable applications. This is why Solana is a popular choice for developers focused on performance. Key endpoints include:

1. getRecentBlockhash. Fetches the latest block hash needed for signing transactions.
2. getAccountInfo. Retrieves account data like balance and ownership.
3. sendTransaction. Submits a transaction to the network.
4. getConfirmedBlock. Retrieves information about a specific confirmed block, including all transactions.
5. getConfirmedSignaturesForAddress2. Fetches signatures for confirmed transactions associated with an address.
6. getSupply. Provides the total supply of SOL, the native token of Solana.
7. getProgramAccounts. Returns all accounts owned by a particular program (smart contract).
8. getTokenAccountsByOwner. Retrieves token accounts owned by a specific public key, useful for querying balances of various tokens.

These endpoints support Solana’s proof-of-history (PoH) system, which timestamps transactions to ensure fast processing. For instance, sendTransaction is imperative for executing trades on DEXs built on Solana. There, low latency is crucial.

Bitcoin API

Bitcoin's API provides essential tools for interacting with the Bitcoin blockchain. They focuse on transaction and wallet management. Key endpoints include:

1. getblockchaininfo. Retrieves the current blockchain state, including block count and difficulty.
2. getrawtransaction. Retrieves detailed transaction information using its ID.
3. getbalance. Returns the balance of a specified wallet address.
4. listunspent. Lists unspent transaction outputs (UTXOs) for a set of addresses, essential for constructing new transactions.
5. sendrawtransaction. Submits a raw transaction (created and signed offline) to the Bitcoin network.
6. getmempoolinfo. Provides information about the nodes' memory pool (mempool), where unconfirmed transactions are held.
7. getblockhash. Retrieves the block hash of a block based on its height, useful for navigating the blockchain.
8. decoderawtransaction. Decodes a raw transaction hex string into a readable JSON object, helping to understand transaction details before broadcasting.

These endpoints are standard in Bitcoin’s JSON-RPC API and are used in various Bitcoin-related development tasks. The getrawtransaction endpoint, for example, is used to verify transaction details before confirmation in a block.

Polygon API

Polygon offers a Layer 2 scaling solution for Ethereum, optimized for lower transaction costs and higher throughput. Key endpoints include:

1. eth_blockNumber. Retrieves the most recent block number.
2. eth_sendTransaction. Sends a transaction to the network with significantly lower gas fees.
3. eth_getLogs. Fetches event logs from the blockchain, useful for tracking smart contract events.
4. eth_getBlockByHash. Fetches block information using the block hash, similar to eth_getBlockByNumber but identified by hash.
5. eth_getUncleByBlockHashAndIndex. Retrieves an uncle block by hash and index position, used in block reward calculations.
6. eth_getStorageAt. Returns the value from a storage position at a specific address, useful for reading smart contract state.
7. eth_newFilter. Creates a filter object to listen for events on the blockchain, such as new blocks or transactions.
8. eth_uninstallFilter. Removes a filter created with eth_newFilter, stopping event listening to reduce resource usage.

These APIs are commonly used in dApps that need Ethereum compatibility but require enhanced performance, particularly in applications dealing with microtransactions where minimizing costs is needed.

Binance Smart Chain (BNB) API

Binance Smart Chain (BSC) runs parallel to Binance Chain, offering smart contract functionality with Ethereum Virtual Machine (EVM) compatibility. Key endpoints include:

• bnb_getTransactionReceipt. Retrieves the receipt of a transaction, including status, gas used, and logs.
• bnb_call. Executes a message call without creating a transaction, similar to Ethereum’s eth_call.
• bnb_getBlockByHash. Returns block information based on the block hash.
• bnb_getLogs. Fetches logs from BSC smart contracts, similar to Ethereum’s eth_getLogs, and is crucial for event tracking.
• bnb_getCode. Retrieves the code at a specific address, helpful for verifying deployed smart contracts.
• bnb_estimateGas. Estimates the gas required for a transaction, aiding in cost prediction on BSC.
• bnb_getStorageAt. Fetches storage data from a specific contract address, allowing for state reading in smart contracts.
• bnb_getTransactionCount. Returns the number of transactions sent from an address, necessary for setting the nonce in new transactions.

These endpoints are must-have things for developers building on BSC. Especially those migrating from Ethereum. The bnb_getTransactionReceipt endpoint, for instance, is used to confirm transaction success before updating user interfaces.