Bitcoin Security Budget — Fee Share of Miner Revenue, Live

Miners are paid two ways: a block subsidy that halves every four years, and transaction fees that depend entirely on demand for block space. This page tracks what share of total miner revenue currently comes from fees — the metric at the center of Bitcoin's long-run security debate.

Data: FeeTotNtv, IssTotUSD, PriceUSD · Coin Metrics community API · computed live in your browser, nothing uploaded

What this chart shows

Every block reward miners receive is made of two parts: the block subsidy (newly issued BTC, currently 3.125 per block) and the sum of transaction fees paid by that block's users. The subsidy is scheduled and predictable; fees depend entirely on how much demand there is for scarce block space. This page converts the day's total fees to USD and expresses them as a share of total miner revenue, where total revenue is reconstructed as issuance value plus fee value (IssTotUSD + FeeTotNtv × PriceUSD), since Coin Metrics' free tier doesn't publish combined miner revenue directly.

Fee Share % = SMA(Daily Fees (USD) / Daily Miner Revenue (USD), 30 days) × 100

As the subsidy keeps halving — it will reach zero entirely around the year 2140 — fees must eventually become the majority, and then nearly all, of what funds mining and therefore network security. This page shows how far that transition has actually progressed, rather than how far theory says it should have.

How to read it

A low reading means network security currently depends almost entirely on the block subsidy — a temporary, scheduled source of income that shrinks by half every four years. A higher, rising reading means fee revenue is taking on more of that load organically, which is the transition the protocol's long-run security model depends on eventually completing.

Limitations

Fee share is extremely event-driven — a single congestion episode (like the 2023 Ordinals inscription surge) can spike this reading sharply and temporarily, then fade completely once the specific demand driver passes. A high reading today doesn't mean fees have durably replaced subsidy.

This metric describes the present composition of miner revenue; it says nothing about whether future fee revenue will actually rise enough, in dollar terms, to replace a shrinking subsidy as issuance approaches zero over the next century-plus. That remains an open, debated question in Bitcoin's long-run security model.

Both fees and subsidy are converted to USD using the same day's price, so a falling BTC price can lower this ratio's dollar-denominated inputs even if the underlying BTC-denominated fee share is unchanged.

FAQ

Why does Bitcoin's security depend on transaction fees eventually?

The block subsidy halves every four years and approaches zero over time (fully exhausted around 2140). Miners must be paid something to keep securing the network, so as the subsidy shrinks toward nothing, fees are the only remaining scheduled source of that payment.

Is Bitcoin's security budget shrinking right now?

In BTC terms, the subsidy is shrinking on a fixed schedule. In USD terms, both subsidy and fees depend on price, which has historically risen enough to keep total miner revenue growing across halvings — but that's a market outcome, not a protocol guarantee, and the Puell Multiple page on this site tracks that revenue directly.

What would resolve the security budget question?

Sustained growth in transaction fee revenue, in dollar terms, large enough to offset the subsidy's decline as it approaches zero. Whether on-chain fee demand (versus fees moving to layers built on top of Bitcoin) will grow enough to do that is genuinely unresolved and actively debated.