getFirstAvailableBlock

getFirstAvailableBlock returns the lowest confirmed slot that the node still holds in its ledger on Solana, the Proof-of-Stake chain whose native token is SOL. Because Solana produces blocks at roughly 400 ms per slot, a non-archival node prunes old history continuously, so this value rises over time and marks the floor of what you can fetch with getBlock, getBlocks, or getBlockTime. Anything below it has been pruned and needs an archival endpoint. The method takes no parameters and returns a single u64. Call it against https://solana.therpc.io/YOUR_API_KEY as a JSON-RPC 2.0 POST.

Use cases

• Know how far back this Solana node can serve before you have to route deeper history requests to an archival endpoint.
• Clamp a historical scan to the available range, so an indexer starts from the first available slot instead of failing on pruned slots below it.

Parameters

هذا الأسلوب لا يأخذ أي معاملات. مرر مصفوفة فارغة [].

Response

Example request

1curl https://solana.therpc.io/YOUR_API_KEY \
2  -X POST \
3  -H "Content-Type: application/json" \
4  -d '{
5  "jsonrpc": "2.0",
6  "id": 1,
7  "method": "getFirstAvailableBlock",
8  "params": []
9}'

Errors & troubleshooting

Common pitfalls

• On pruned (non-archival) nodes this floor keeps rising as old slots are dropped, so a block that was reachable yesterday may sit below it today — older history needs an archival endpoint.
• This is the first available block, which is not necessarily the same as minimumLedgerSlot. Use minimumLedgerSlot if you specifically need the lowest slot present in the raw ledger.

Supported networks

• Mainnet
• Devnet

See also

• minimumLedgerSlot
• getBlocks