How Lightning routing fees work
Every node on a payment route sets its own fee policy: a flat base fee plus a proportional rate in ppm (parts per million) of the amount it forwards. Your wallet sums these across every hop to build the route. Because the proportional part is tiny (often 0–500 ppm) and the base fee is usually ≤1 sat, routing a typical payment costs a fraction of a cent — far below the flat, size-independent cost of an on-chain Bitcoin transaction. For the on-chain side, use the Bitcoin transaction fee tool. To convert between sats, BTC and USD, use the Satoshi converter.
Lightning vs on-chain: where the crossover sits
The Lightning fee formula per hop is fee = base_fee + amount × fee_rate_ppm ÷ 1,000,000, summed over every hop in the route. The base fee component is flat and tiny; the ppm component scales with the amount sent. An on-chain transaction, by contrast, costs vBytes × sat/vByte regardless of how many sats are being moved. For small and mid-size payments, Lightning wins by orders of magnitude — sending $50 in sats might cost a fraction of a cent in routing fees versus a few dollars on-chain during normal congestion.
As the payment size grows, the ppm component of Lightning fees grows with it, while the on-chain fee stays flat. That creates a breakeven amount: below it, Lightning routing is cheaper; above it, a single on-chain transaction can end up cheaper, especially over routes with several hops or nodes charging above-average ppm rates. This calculator solves for that breakeven directly from your fee inputs, so you can see where the two curves cross for your own assumptions.
In practice, actual routing fees depend on real-time channel liquidity, the number of hops your wallet's pathfinding picks, and each node's individually configured policy — so treat this as a mechanic-level estimate, not a quote from a specific route. Multi-part payments (splitting a large payment across several smaller routes) can also change the effective total versus a single route.