How we compare

How this site works

JustaHeater.lol compares bitcoin heaters, home miners and industrial miners side by side. As well as hashrate and price, it shows the things that matter when a miner lives in your home: heat, noise, size and what a kWh of heat really costs. Right now that's 208 devices from 27 brands, with 433 prices from 32 stores.

• Independent. We're not a shop and we don't sell anything. No maker or store pays to be listed, and nobody can pay to rank higher. Our "top picks" are worked out from the numbers.
• Not sponsored. Links to stores are plain links, not affiliate links. We earn nothing when you buy.
• Prices with dates. We take every price from the store's own listing (its product page or the shop's public catalogue) and note the day we checked it (most recently 12 Nov 2026). Prices leave out shipping, and often tax and import duty. They change often, so always check the store.
• In your currency. We keep each price in the store's own currency and convert it with the European Central Bank's reference rates (from 11 Nov 2026). We start with the currency that fits your browser's time zone and language, without sending them anywhere. Pick another at the top of any page and we'll remember it.
• Estimates are labelled. Heat, room size, running cost and mining income are estimates, and we say so wherever they appear.

What the numbers mean

Hashrate (TH/s)

How many guesses at the next bitcoin block a device makes each second, in trillions (terahashes). 1 TH/s is 1,000 GH/s; 1,000 TH/s is 1 PH/s. More hashrate earns more sats.

Power (W)

What the device draws from the wall at the maker's standard (stock) setting. Some have lower, quieter modes, and some can be overclocked to draw more (see Heat modes on the device page).

Efficiency (J/TH)

Joules per terahash: power divided by hashrate. Lower is better: less electricity for the same mining. We use the maker's figure where there is one and work it out otherwise.

Earnings per kWh

What a device earns for each kWh of electricity it uses, before paying for it. Higher is better, and it needs to beat your electricity price for mining to cover its running cost. How we work it out.

Heat output (BTU/h)

Power × 3.412. A 1,000 W miner gives out 3,412 BTU/h, the same as a 1,000 W fan heater. [1]

Price per TH

The best price divided by the hashrate: how much mining you get for your money. It says nothing about heat, so a quiet, well-made heater can look pricey here and still be the right buy.

Production status

In production: made and sold now. Pre-order: you pay now and it ships later. Announced: revealed but not on sale yet. Discontinued: no longer made, though you may still find stock or used units. Unknown: we couldn't confirm.

Form factor

Desktop sits on a desk or shelf; floor standing stands on the floor like a tower heater; wall mounted hangs like a panel radiator; rack / shelf is how industrial machines are usually installed.

Device groups

Every device is in one of six groups. Each has its own colour and shape on the charts.

• Space heaters (circle): made to warm a room. Ready-made heaters, and kits that turn a miner into one.
• Water heaters (diamond): tank heaters, boilers, heating elements and pool or hot-tub heaters that put the heat into water, for hot taps, radiators, underfloor heating or a pool.
• Air filters (hexagon): air purifiers with a small miner inside. They're there to clean the air, and give off very little heat.
• Home (square): small plug-in miners for a desk or shelf, such as FutureBit Apollos, Braiins Minis and USB sticks.
• Bitaxe miners (down triangle): "lottery" miners built on the open-source Bitaxe design: official Bitaxe boards, open-source forks such as NerdAxe, and clones that run the Bitaxe firmware (AxeOS).
• Industrial (up triangle): data-centre machines. Loud, power-hungry and efficient: good heat for a workshop, garage or greenhouse, and often in need of a dedicated circuit.

Noise (dB)

As stated by the maker or a store. They rarely say how far away they measured or in which mode, so treat it as a guide. 30 dB is a whisper and the WHO's guideline for bedrooms at night; 60 dB is a normal conversation. [19][20] Every extra 10 dB sounds about twice as loud. [21]

Area heated

The maker's claim where there is one, marked as such. Otherwise it's our estimate from the device's power: see heat and room size.

Hot water

Water heaters get this instead of an area: how many litres an hour the device could warm from 10 °C mains water to 50 °C if all its heat went into the water. 1 kWh warms 860 litres by 1 °C, or 21.5 litres by 40 °C, so a 600 W unit (0.6 kWh an hour) manages about 13 litres an hour. Tanks lose some heat, so treat it as an upper bound for that 40 °C rise. A maker's "recovery rate" may assume a different rise, so it isn't directly comparable.

Availability and condition

In stock, pre-order, out of stock, or check store when the page didn't say. Condition is new, refurbished or used.

TrustScore

Trustpilot's 1 to 5 score for the store that sells the device. It's about the store's service, not the device. See reviews and Trustpilot.

* An asterisk on a spec

We haven't confirmed that figure from the maker's own documents yet. It came from a store, a review or our own sums.

Heat and room size

Every watt a miner draws ends up as heat in the room, just like an ordinary electric heater. Its chips and fans turn electricity into heat, and the tiny bit that leaves as sound and light doesn't matter. [2] So heat output is simply the power in watts × 3.412 BTU per hour. [1][3]

Heat only helps where you want it. A miner that blows its exhaust into the loft or out of a window warms the room much less. [4]

How much room it can warm

To estimate the floor area a device can keep warm on its own on a cold day, we divide its power by the watts each square metre needs. That depends a lot on insulation, so we use these bands from UK, US and German heating guides:

Space heater and miner pages show a range: from a draughty room (150 W/m²) to a well-insulated one (50 W/m²), with a typical room (100 W/m²) in the middle. Water heaters put their heat into water, so their pages show litres of hot water an hour instead (see Hot water above). The heat calculator lets you pick your own band and room size.

• These are cold-day figures. Most winter days are milder, so a device can keep a bigger room warm than this most of the time. [5]
• Proper sizing uses a room-by-room heat-loss calculation (BS EN 12831, or MCS 031 in the UK). Rules of thumb are a starting point, not a design. [5][6]
• Under about 300 W, think of a device as a top-up for a room, not its only heat.

Compared with a heat pump

A bitcoin heater makes heat exactly as efficiently as a plain electric heater; the bitcoin it earns is a discount on the bill. A heat pump makes 2–3 times as much heat from each kWh (a median of 2.8 in a big UK field trial, and often 3–4 in lab tests), so for heating a whole home it's usually the cheaper choice. A bitcoin heater makes most sense where you'd use an electric heater anyway: a room without central heating, a garage or home office, or a rented home where you can't fit a heat pump.

The example prices are close to the UK price cap for October to December 2026 (about 26p) [17] and the US average for 2026 (about 18¢). [18] To match a heat pump at these figures, a miner would need about 6.1 J/TH in the UK or 11.8 J/TH in the US. The most efficient home device in our database uses 9 J/TH. Try your own tariff in the heat calculator.

How we estimate mining income

Mining income is an average, not a promise. We use the same standard method as the industry's "hashprice" figures: [13]

sats per day =equals hashrate (H/s) × 86,400 × reward per block ÷divided by (difficulty × 2³²)

• Difficulty × 2³² is how many hashes the whole network needs, on average, to find one block. [14] On 12 Nov 2026 the difficulty was 148.36 trillion.
• Reward per block is the subsidy (3.125 BTC until the next halving) plus the average transaction fees over the last 144 blocks, about a day. On 12 Nov 2026 that was 3.1518 BTC a block, of which 0.0268 BTC was fees.
• Bitcoin price turns sats into your currency. All three come from mempool.space. [16]

Pages fetch fresh figures from mempool.space in your browser and keep them for ten minutes. If mempool.space can't be reached, we use the snapshot saved when the site was last built, and say so. At the 12 Nov 2026 snapshot, each TH/s earned about 42.7 sats a day (about $0.031), before pool fees.

Pool or solo

Payback

Payback is how long the bitcoin a device earns takes to add up to its price. Each day adds its mining income, until that reaches the price:

best price =equals days × mining income a day

• Mining income here isn't the live figure above. It uses the average of the last 3 months, so one day's price swing doesn't change the answer: the device's share of the network's hashrate, times 144 blocks a day, the reward per block and the bitcoin price, less a 2% pool fee. To 12 Nov 2026 that was $79,558 a bitcoin, 969 EH/s and 3.15 BTC a block, or about $0.036 per TH/s a day.
• Halvings cut that income, and the sum carries on from there at the lower figure. Each one halves the block subsidy, but fees carry on, so the next one, around April 2028, leaves 50.3% of the income. They then come about every four years.
• Electricity isn't counted. A bitcoin heater turns it into the same heat a plain electric heater would, so the bitcoin is what pays for the device. Whether mining alone covers the electricity is a separate question, which earnings per kWh answers.
• Running time is all day, every day of the year. On a device page it runs for the hours you set, and the income falls to match.
• Best price is the same one the tables show, and the hashrate is for the unit that price buys, where the store says which. Where a price leaves something out, such as the power supply, the figure starts with ≥.

"Never" means it doesn't earn back its price within 30 years. Halvings shrink the income so much that 30 years earns only about 5.5 years of today's income, so a device that would take longer than that at today's income never gets there. They're mostly small devices with a high price for their hashrate.

A room heater runs only through a heating season, so it takes far longer than running all year. The calculator works that out: it counts only the sats, over your heating days, for the heat your room takes.

Payback is a rough guide, because it holds the bitcoin price, the hashrate and fees at those averages, and they won't stay there. Hashrate usually rises and the bitcoin price moves. A halving could shift both: at half the income some miners stop paying and switch off, which leaves more for the rest, and we don't count that, or any rise in the price. So a long figure, or a "Never", may be too harsh. The longer the payback, the less it means. It also ignores repairs, shipping and tax.

Earnings per kWh

Earnings per kWh is what a device earns for each kWh of electricity it uses, before paying for that electricity:

earnings per kWh =equals income per TH/s a day ÷divided by (J/TH × 24 ÷ 1,000)

It uses the same 3-month averages and 2% pool fee as payback, which makes it about $0.076 for a 20 J/TH miner. The J/TH here is the device's power divided by its hashrate, so it counts everything the device draws. That can differ a little from the maker's own figure, or a lot where that figure covers only the chips. Set it against your electricity price: if a device earns less per kWh than you pay, mining doesn't cover its running cost, however little it cost to buy. It only depends on efficiency, so neither the device's price nor the hours it runs change it.

It answers a different question from payback. Payback leaves out electricity, because a heater turns it into heat you'd pay for anyway; earnings per kWh says whether the mining alone covers that electricity. The next halving, around April 2028, leaves about 50% of this figure.

Fees, difficulty and the halving

• Transaction fees go up and down with demand, so we use the average of the last 144 blocks.
• Difficulty adjusts every 2,016 blocks, about every two weeks. It has tended to rise as more miners join, which shrinks everyone's share. [14]
• The subsidy halves every 210,000 blocks. It is 3.125 BTC until block 1,050,000, expected around April 2028, and then 1.5625 BTC. [15]
• Income is paid in bitcoin, and its price can fall as well as rise.
• Heat is only worth having in the heating season. Run a miner in summer and you pay for heat you may then have to get rid of.

Reviews and Trustpilot scores

Reviews from Nostr

Reviews on device pages are posted on Nostr, an open network for sharing notes. There's no company in the middle: your account is a pair of keys, and your posts are copied to servers called relays that anyone can run.

• Signing in. Press Sign in at the top of any page. Use a Nostr browser extension, such as Alby or nos2x, or a signer app on your phone, such as Amber. It keeps your private key and signs your review for you, so this site never sees it.
• Your review is yours. It's a public note signed with your key. It belongs to you, not to us, and other Nostr apps can show it too.
• Taking it down. Delete it on the device page, or send a deletion request from any Nostr app: once the request reaches one of the review relays, this site stops showing the review. Most relays honour the request too, but not every relay does.
• We don't check purchases or names. Anyone with a Nostr key can post a review under any name, so each review also shows the start and end of the reviewer's key (npub). Read them as you would anywhere: detail and photos count for more than stars.
• Reporting a review. If a review is abusive, unlawful or pretends to be someone it isn't, email winky@justaheater.lol with a link to the device page and the reviewer's name. We can hide a review or a reviewer on this site, though not from Nostr itself.
• New to Nostr? Any Nostr app can make you a pair of keys in a minute. Keep the private key (it starts with nsec) safe: anyone who has it can post as you.

Trustpilot scores

TrustScores come from Trustpilot and belong to Trustpilot. They rate a store's service, such as delivery, support and refunds, not the device. We take each store's score and review count from its Trustpilot page and show when we checked (most recently 10 Nov 2026). A missing score means the store has no Trustpilot page or we haven't checked it yet. See them all on the stores page.

Privacy

There are no ads, trackers or cookies here, and the fonts and scripts come from this site. Your choices (theme, currency, compare list, review drafts and your Nostr sign-in) stay in your own browser. A few things do mean your browser talks to other servers, which can see your IP address as any website can:

• Live network figures come from mempool.space, on the home, device, compare and calculator pages.
• Reviews. When you scroll down to the reviews on a device page, your browser asks the review relays (nos.lol, relay.primal.net, relay.damus.io and nostr.mom) for that device's reviews, so they can tell which device you're looking at. Reviewers' names come from purplepag.es, relay.primal.net, relay.damus.io and nos.lol.
• Profile pictures load only from well-known Nostr image hosts (nostr.build, primal.net, primal.b-cdn.net, nostrcheck.me, void.cat, imgur.com, blossom.band and satellite.earth). A reviewer whose picture is anywhere else gets a letter instead, so a reviewer can't use their picture to log who reads their review.
• Signing in. The sign-in box connects to relay.nostrconnect.com, relay.primal.net and nos.lol so a signer app can reach it, and a signer link you paste names its own relays. While you're signed in, your public key is looked up on the profile relays once per visit to show your name, and your reviews also go to up to three of your own Nostr relays.
• Store links are plain links: the store only knows you came from here if you follow one.

Our price bot

JustaHeaterPriceBot visits some of the stores we list about once a day, to check the price and stock of the products we link to. It says who it is, follows each store's robots.txt, waits at least 3 seconds between requests, and stops for the day if a store refuses it. It doesn't log in, buy anything, or try to get past a block.

We leave out stores whose terms forbid this or limit reusing their data. Their prices are checked less often and keep the date of their last check.

Run a store? If you'd like yours left out, or would rather give us a feed, email winky@justaheater.lol.

Disclaimer

• Not financial advice. JustaHeater.lol compares heaters. It isn't financial, investment or tax advice. Bitcoin is volatile: mining income can go down as well as up, and can be zero.
• Prices change. Prices and stock come from retailers and can change at any time. Check the store before you buy. Links to stores are not affiliate links: we earn nothing when you buy.
• Estimates. Heat, room size, running cost, mining income and payback are estimates. They use rule-of-thumb maths, the device's stated power, your tariff and live network data. Your results will vary.
• Live data. Live figures come from mempool.space and are cached for a few minutes. If they can't be reached, we show the last saved figures and say so.
• Heat pumps. For whole-home heating, a heat pump usually makes 2–3× more heat per kWh. A bitcoin heater makes the most sense where you'd use an electric heater anyway.
• Specs and noise. Specs come from manufacturers and retailers and are not always measured the same way. Noise depends on distance, mode and room.
• Safety. Plug miners into a suitable socket or circuit, keep vents clear, and follow the maker's instructions. Big industrial miners are loud and can need a dedicated circuit.
• Reviews. Reviews are posted by users signed in with Nostr. We don't verify purchases. Trustpilot scores belong to Trustpilot and refer to the store, not the device.

Suggest a device or fix a mistake

The database is only as good as its sources, and we'd love your help. Tell us about a device we've missed, a price that's out of date, or a spec that's wrong.

Please include:

• the brand and model;
• what's wrong or missing, or which device you'd like added;
• a link to where you found it: the maker's spec sheet or manual is best, or a store page that sells it.

Credits and data sources

Device specs

Makers' own spec sheets, manuals and product pages, then store listings. Each device page lists its sources.

Prices and stock

Each store's own listings, checked on the dates shown.

Bitcoin network

mempool.space: difficulty, block rewards, fees and the bitcoin price.

Exchange rates

European Central Bank reference rates, via frankfurter.dev (last updated 11 Nov 2026).

Store ratings

TrustScores and review counts from Trustpilot (checked 10 Nov 2026).

Reviews

The Nostr users who write them, and the relays that carry them.

Fonts

Inter Tight, under the SIL Open Font License.

Heating and noise figures

The guides and studies listed below.

References

1. British thermal units (Btu). US Energy Information Administration. eia.gov
2. Electric resistance heating. US Department of Energy, Energy Saver. energy.gov
3. Mining heater comparison. D-Central, which sells mining heaters. d-central.tech
4. Bitcoin mining heat recovery. D-Central, which sells mining heaters. d-central.tech
5. Heat loss calculations. Heat Geek. heatgeek.com
6. Heat-pump sizing guides: watts per m² by the age of the house. UK installers and calculators. autarc.energy · renewableheatinghub.co.uk · heatable.co.uk
7. Electric radiator sizing guides. UK retailers. electricradiatorshop.co.uk · trustelectricheating.co.uk · qssupplies.co.uk
8. Space heater sizing guides. US retailers. sylvane.com · mepacademy.com · pickhvac.com
9. Heizlast guides: watts per m² by building age. Enpal, 42watt and EcoFlow (in German). enpal.de · 42watt.de · ecoflow.com
10. Heizlast im Niedrigenergie- und Passivhaus. Baunetz Wissen (in German). baunetzwissen.de
11. Heat pumps shown to be three times more efficient than gas boilers. Energy Systems Catapult, Electrification of Heat trial. es.catapult.org.uk
12. Air source heat pump efficiency (SCOP ranges). EDF Energy and Selectra. edfenergy.com · selectra.co.uk
13. Hashprice. Luxor, Hashrate Index documentation. docs.luxor.tech
14. Difficulty. Bitcoin Wiki. en.bitcoin.it
15. Controlled supply. Bitcoin Wiki. en.bitcoin.it
16. REST API documentation. mempool.space. mempool.space
17. Changes to energy price cap between 1 October and 31 December 2026. Ofgem. ofgem.gov.uk
18. Short-Term Energy Outlook: electricity. US Energy Information Administration. eia.gov
19. Levels of noise in decibels (dB). American Academy of Audiology (2023). audiology.org
20. WHO guidelines for community noise: a help or a hindrance? Institute of Acoustics proceedings, on the WHO 1999 guidelines. ioa.org.uk
21. Decibel (loudness) comparison chart. HearingConservation.org. hearingconservation.org
22. Noise-induced hearing loss. NIDCD, US National Institutes of Health. nidcd.nih.gov