Methodology
The sources, the formulas and the assumptions. If you can reproduce the number yourself, you do not have to trust us for it.
Daily revenue is your share of the network, times what the network pays out, times the coin price, less the pool fee:
revenue/day = (your hashrate ÷ network hashrate) × blocks per day × block reward × GBP price × (1 − pool fee)
Pool fee is held at 1%. Block rewards and blocks-per-day are held as constants per coin and re-checked quarterly, because rewards decay on their own schedules — Kaspa monthly, Ergo on a fixed curve — and block times drift.
Rates come from the Octopus Energy public API for the Agile tariff (AGILE-24-10-01), pulled live for the region you select. All 14 UK distribution regions are supported, from Eastern England through to Northern Scotland. Prices used are inclusive of VAT, at half-hourly granularity — 48 different prices a day, which is the whole point: a rig does not cost one price to run.
The standing charge is fetched from the same API and shown separately, because you pay it whether the rig runs or not. Most calculators omit it entirely, which materially overstates profitability for small operations. If the API is unreachable we fall back to a stored figure of 48.79p per day and the page says so rather than pretending the number is live.
In winter, an optional 70% heat credit can be applied, on the basis that a rig in a room you were heating anyway displaces that heating. Switch it off if that does not describe your setup — it materially changes the answer.
Hashrate is read live, per chain, from the operators of those chains or from established public explorers: mempool.space for Bitcoin, litecoinspace.org for Litecoin, api.kaspa.org for Kaspa, api.ergoplatform.com for Ergo, 2miners for Ravencoin and Ethereum Classic, and xmrchain.net for Monero. Where an endpoint is unavailable, a stored fallback is used and the page marks the figure as not live.
Coin prices in GBP come from CoinPaprika, which also drives the ticker across the top of every page.
The estimator implements the 2026/27 rules, verified against HMRC and House of Commons Library published rates. The constants it uses:
| Personal allowance | £12,570, tapering £1 for every £2 of income over £100,000 |
| Basic rate band | £37,700 above the personal allowance |
| Higher rate limit | £125,140 |
| Income tax | 20% / 40% / 45% |
| Capital gains allowance | £3,000 |
| Capital gains rates | 18% inside the basic rate band, 24% above it |
| Trading allowance | £1,000, covering small miscellaneous mining receipts |
The point most crypto tax tools get wrong, and this one does not: capital gains do not have their own independent rate. They stack on top of your taxable income. Whatever portion of the gain still falls inside the basic rate band is charged at 18%; everything above it at 24%. Two people with identical gains and different salaries owe very different amounts.
Naming the gaps matters more than hiding them. It does not implement HMRC's share-matching rules — the same-day rule, the 30-day “bed and breakfasting” rule, or Section 104 pooling — so it will not compute your cost basis across many disposals of the same asset. It does not carry losses forward, handle transfers between your own wallets, or cover anything outside the 2026/27 year.
It is a way of understanding the shape of a liability, not a substitute for a return. For anything that turns on your circumstances, use it as the start of a conversation with an accountant.
Hashrate and wall-power figures in the hardware reviews start from the manufacturer's published specifications and are adjusted to what the machines actually reach in use — typical tuned figures, measured at the wall rather than at the PSU. Stock headline numbers and real running figures are not the same thing, and the gap between them is where a good many mining forecasts go wrong.
Where a figure has been adjusted away from spec, it is the adjusted figure that feeds the profitability calculation, because that is the one that determines what you actually pay. Efficiency in J/TH is derived from those same figures rather than quoted separately.
These are estimates from stated assumptions, not predictions. Difficulty is treated as constant over a projection; in reality it moves, and rising difficulty is where most optimistic mining forecasts go wrong. Crypto assets are not covered by the Financial Services Compensation Scheme and are not regulated for consumer protection in the UK.
If a calculation looks wrong, tell us and we will check it: hello@cryptogrid.co.uk. The editorial policy sets out what happens next.