Energy efficiency
17.5 J/TH
3,500 W ÷ 200 TH/s
#59 of 99 in the catalog
ASIC miner · Bitmain
Bitmain Antminer S21
An air-cooled Bitcoin ASIC with 200 TH/s at 3,500 W — 17.5 J/TH.
About Antminer S21
The Antminer S21 is Bitmain's air-cooled model, released in September 2023. At 17.5 J/TH it ranks #59 of 99 in the catalog by efficiency, and 19th of 48 among air-cooled machines.
At 76 dB and 3.5 kW it needs a data center or a dedicated ventilated room, not a living room.
What the specs add up to
Derived from the specs below, with the formula on every card. Estimates, not a forecast
Electricity used per day
84.0 kWh
3.50 kW × 24 h
30.7 MWh a year
Electricity cost per day
$8.40
84.0 kWh × $0.10 per kWh
Break-even electricity price
$0.072 / kWh
Estimated daily reward ÷ electricity used per day
As of 13 Nov 2026
Built for
Data center
76 dB, 3.50 kW of heat
Home class: up to 50 dB and 1.4 kW, air cooling
Hashrate per kW
57.1 TH/s
200 TH/s ÷ 3.50 kW
Antminer S21 or a digital miner with the same 200 TH/s
Same hashrate, side by side. Scenario: you run the machine yourself, on household electricity. Numbers follow our reward calculator and update daily
BTC price · 13 Nov 2026$70,780
Antminer S21
Your own machine · 200 TH/s · 17.5 J/TH
- Upfront cost
- Not shownNot in the catalog yet — see the manufacturer's store
- Reward per day (est.)
- 0.00009 BTC≈ $6.02 at the same hashrate
- Running cost per day
- $8.403.50 kW × 24 h × $0.10 per kWh
- Net per day (est.)
- −$2.38At your electricity price
- Delivery and setup
- Shipping, customs, pool setup
- Noise and heat
- 76 dB and 3.50 kW of heat at your place
GoMining digital miner
200 TH/s · 15 J/TH · runs in our data centers
- Upfront cost
- $2,294200 TH × $11.47 per TH
- Reward per day (est.)
- 0.00009 BTC≈ $6.02
- Running cost per day
- $5.38Daily maintenance fee: electricity and service
- Net per day (est.)
- $0.64After the maintenance fee
- Delivery and setup
- Nothing to ship — runs in the app
- Noise and heat
- Nothing at your place
Break-even electricity price for this model: $0.072 per kWh. Above it, electricity costs more than the estimated reward
Estimates, not a forecast. Based on the BTC price, network difficulty and GoMining fees as of 13 Nov 2026; specs as published by the manufacturer. Assumes the machine runs 24/7 with no pool fee; industrial hosting is a different calculation. The digital miner's fee is shown before discounts. Mining rewards vary and are not guaranteed; they may fall below fees. Not investment advice. See terms
Antminer S21 specifications
16 characteristics, each with its source and the date we checked it. Values are nominal, as published by the manufacturer
- Published spec
- Calculated by GoMining
- Not found
- Manufacturer
- Bitmain
- Model
- Antminer S21
- Algorithm
- SHA-256 (Bitcoin)
- Energy efficiency
- 17.5 J/TH
- Calculated
- Sold by manufacturer
- —
- Not found · 16 Oct 2026
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Preguntas frecuentes
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