Antminer S21 Pro

Hashrate 234.0 TH/s Power 3,510 W Efficiency 15.0 J/TH

Bitdeer SealMiner A2 Hyd

Hashrate 446.0 TH/s Power 7,360 W Efficiency 16.5 J/TH

Antminer S21 Pro vs Bitdeer SealMiner A2 Hyd

Side-by-side specs, profitability, and home mining comparison.

Specifications Comparison

Antminer S21 Pro	Specification	Bitdeer SealMiner A2 Hyd
234.0 TH/s	Hashrate	446.0 TH/s
3,510 W	Power Consumption	7,360 W
15.0 J/TH	Efficiency	16.5 J/TH
75 dB	Noise Level	50 dB
15.0 kg	Weight	20.5 kg
11,976 BTU/hr	BTU Output	25,112 BTU/hr
30/100	Home Mining Score	44/100
—	Release Year	—
SHA-256	Algorithm	SHA-256
Bitmain	Manufacturer	Bitdeer

Profitability Comparison

Electricity Rate:

$/kWh

Antminer S21 Pro

Daily Revenue 0.00010768 BTC $8.51

Daily Electricity -$8.42

Daily Profit $0.09

Monthly $2.65

Yearly $32.28

Bitdeer SealMiner A2 Hyd

Daily Revenue 0.00020524 BTC $16.22

Daily Electricity -$17.66

Daily Profit -$1.44

Monthly -$43.18

Yearly -$525.40

Based on BTC price of $79,051 and current network difficulty as of May 15, 2026. Actual results vary.

Verdict

Weighing six performance factors, the Bitdeer SealMiner A2 Hyd comes out ahead — it takes 4 of 6 (hashrate, home mining score, noise level, price-performance). Its biggest concrete edge: 91% more hashrate (234 vs 446 TH/s). That said, the Antminer S21 Pro isn't beaten everywhere — it still wins efficiency and power consumption. Cross-check the spec deltas and ROI table above against your own electricity rate before deciding.

Winner: Bitdeer SealMiner A2 Hyd — wins on 4 of 6 factors

Spec Deltas

The Antminer S21 Pro and Bitdeer SealMiner A2 Hyd diverge on the metrics below — each gap expressed as a real percentage, not a vague "better":

Bitdeer SealMiner A2 Hyd 91% more hashrate (234 vs 446 TH/s)
Antminer S21 Pro 52% better power draw (3,510 vs 7,360 W)
Antminer S21 Pro 9% better efficiency (15.0 vs 16.5 J/TH)
Bitdeer SealMiner A2 Hyd 33% better noise (75.0 vs 50.0 dB)
Antminer S21 Pro 27% better weight (15.0 vs 20.5 kg)
Bitdeer SealMiner A2 Hyd 110% more heat output (11,976 vs 25,112 BTU/hr)
Bitdeer SealMiner A2 Hyd 47% more home mining score (30.0 vs 44.0)

Cost & ROI Over Time

Hardware cost is only half the story — here is how each miner's upfront price plays out against cumulative profit at a $0.10/kWh rate.

Antminer S21 Pro	Metric	Bitdeer SealMiner A2 Hyd
$6,800	Upfront cost (MSRP)	$6,150
$0.09	Daily net profit	-$1.44
-$6,768	Net after 1 year	-$6,675
-$6,735	Net after 2 years	-$7,201
-$6,703	Net after 3 years	-$7,726
Takes ~210.7 years to pay back at current rates	Payback period	Does not pay back at current rates (negative daily profit)

Projections assume continuous operation, a flat $0.10/kWh rate, and no hardware degradation, pool fees, or BTC price change. Real-world ROI varies.

Best For...

Best for Profitability

Antminer S21 Pro

$1.53/day higher profit at current rates.

Best for Home Mining

Bitdeer SealMiner A2 Hyd

Score: 44/100. 50 dB noise level.

Best for Efficiency

Antminer S21 Pro

15.0 J/TH — lower electricity cost per terahash.

Frequently Asked Questions

Which makes more money, the Antminer S21 Pro or the Bitdeer SealMiner A2 Hyd?

At the current BTC price and a $0.10/kWh electricity rate, the Antminer S21 Pro is more profitable at $0.09/day compared to $-1.44/day for the Bitdeer SealMiner A2 Hyd. Profitability depends heavily on your electricity rate — use the selector above to calculate with your actual costs.

Antminer S21 Pro vs Bitdeer SealMiner A2 Hyd: which runs at a lower noise level?

The Bitdeer SealMiner A2 Hyd is quieter at 50 dB compared to the Antminer S21 Pro at 75 dB. For home mining, lower noise levels make a significant difference in livability.

Which is better for home mining, the Antminer S21 Pro or Bitdeer SealMiner A2 Hyd?

The Bitdeer SealMiner A2 Hyd scores 44/100 on our Home Mining Score (vs 30/100 for the Antminer S21 Pro). This composite score factors in noise, power requirements, heat output, size, and setup ease — all critical for residential mining.

How far apart are the Antminer S21 Pro and Bitdeer SealMiner A2 Hyd on J/TH?

The Antminer S21 Pro runs at 15.0 J/TH while the Bitdeer SealMiner A2 Hyd runs at 16.5 J/TH — a difference of 1.5 J/TH. Lower efficiency means less electricity per terahash of mining power, directly reducing operating costs. In relative terms that is 9% better efficiency (15.0 vs 16.5 J/TH).

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