beefy_getFinalizedHead - Bifrost RPC Method

Returns the block hash of the latest BEEFY-finalized block on Bifrost. BEEFY (Bridge Efficiency Enabling Finality Yielder) provides additional finality proofs that are optimized for light clients and cross-chain bridges, using compact aggregated signatures instead of full GRANDPA justifications.

Why Bifrost? Build on Polkadot's largest liquid staking appchain with 60% DOT LST market share and $125M+ TVL with first LST governance on OpenGov, 60% DOT market share, Hyperbridge ETH integration, and 500K DOT treasury support.

When to Use This Method

beefy_getFinalizedHead is important for liquid staking developers, DeFi builders, and teams requiring cross-chain yield solutions:

• Cross-Chain Bridges — Verify finality proofs efficiently for bridge operations on omnichain liquid staking (vDOT, vKSM, vGLMR, vMOVR, vASTR), cross-chain vToken governance, and DOT/ETH liquidity bridging
• Light Clients — Verify finality without downloading full GRANDPA justifications
• Trustless Bridges — Generate compact finality proofs that can be verified on external chains
• Bridge Monitoring — Track BEEFY finality progress relative to GRANDPA finality

Code Examples

Common Use Cases

1. Bridge Finality Verification

Verify BEEFY finality before relaying messages on a cross-chain bridge:

async function verifyBridgeFinality(api, targetBlockHash) {
  const beefyHead = await api.rpc.beefy.getFinalizedHead();
  const beefyBlock = await api.rpc.chain.getBlock(beefyHead);
  const beefyNumber = beefyBlock.block.header.number.toNumber();

  const targetBlock = await api.rpc.chain.getBlock(targetBlockHash);
  const targetNumber = targetBlock.block.header.number.toNumber();

  if (beefyNumber >= targetNumber) {
    console.log(`Block #${targetNumber} has BEEFY finality — safe to relay`);
    return true;
  } else {
    console.log(`Waiting: BEEFY at #${beefyNumber}, target at #${targetNumber}`);
    return false;
  }
}

2. BEEFY vs GRANDPA Finality Monitor

Track the gap between the two finality gadgets:

async function monitorFinalityGadgets(api) {
  setInterval(async () => {
    try {
      const [beefyHead, grandpaHead] = await Promise.all([
        api.rpc.beefy.getFinalizedHead(),
        api.rpc.chain.getFinalizedHead()
      ]);

      const [beefyBlock, grandpaBlock] = await Promise.all([
        api.rpc.chain.getBlock(beefyHead),
        api.rpc.chain.getBlock(grandpaHead)
      ]);

      const beefyNum = beefyBlock.block.header.number.toNumber();
      const grandpaNum = grandpaBlock.block.header.number.toNumber();
      const lag = grandpaNum - beefyNum;

      console.log(`GRANDPA: #${grandpaNum} | BEEFY: #${beefyNum} | Lag: ${lag} blocks`);
    } catch (error) {
      console.error('Monitor error:', error.message);
    }
  }, 12000);
}

BEEFY vs GRANDPA Finality

Availability

BEEFY is enabled on Polkadot and Kusama relay chains and some parachains. If BEEFY is not active on the chain you are querying, this method will return an error. Check chain documentation or try calling the method to confirm availability.

Error Handling

Related Methods

• chain_getFinalizedHead — Get GRANDPA finalized head
• grandpa_roundState — Monitor GRANDPA consensus state
• chain_subscribeFinalizedHeads — Subscribe to GRANDPA finalized blocks