Miner comparison
Antminer S21 XP vs SEALMINER A3 Pro Air
Both are air-cooled machines for SHA-256 (Bitcoin) mining, specified for a 220–277 V AC supply, rated at 25 °C and specified for -20 to 45 °C operation. Bitmain rates the Antminer S21 XP at 270 TH/s on 3,645 W (13.5 J/TH); Bitdeer rates the SEALMINER A3 Pro Air at 290 TH/s on 3,625 W (12.5 J/TH). The A3 Pro Air gives about 7% more hashrate on 20 W less power, so each terahash takes about 7% less electricity. The S21 XP draws up to 20 A, the A3 Pro Air up to 27 A. The Bitdeer unit measures 197 × 365 × 292 mm and weighs 15.5 kg net; the S21 XP measures 450 × 219 × 293 mm and weighs 18.7 kg. Bitmain rates the S21 XP at 76 dBA; Bitdeer publishes no noise figure. The table below and the calculator work out what these figures mean with current network data.
Figures: Bitmain and Bitdeer specification pages for Antminer S21 XP and SEALMINER A3 Pro Air, checked 2026-10-10.
| Compare |  Bitmain Antminer S21 XPAvailable |  Bitdeer SEALMINER A3 Pro AirAvailable |
|---|---|---|
| Price | ||
| Price | $2,944.05 | $4,654.05 |
| Price per TH/s | $10.90/TH | $16.05/TH |
| Condition | New | New |
| Specifications | ||
| Hashrate | 270 TH/s (±3%) | 290 TH/s (±10%) |
| Power consumption | 3,645 W (±5%) | 3,625 W (±10%) |
| Efficiency | 13.5 J/TH | 12.5 J/TH |
| Algorithm | SHA-256 | SHA-256 |
| Input voltage | 220–277 V AC | — |
| Electrical phase | Single-phase | — |
| Cooling type | Air-cooled | Air-cooled |
| Noise level | 76 dB | — |
| Dimensions (L × W × H) | 450 × 219 × 293 mm | — |
| Net weight | 18.7 kg | — |
| Operating temperature | -20–45 °C | — |
| Release date | — | September 16, 2025 |
| Operating economics | ||
| Electricity cost / day at $0.06/kWh | $5.25 | $5.22 |
| Est. revenue / day | $9.58 | $10.29 |
| Est. net / day at $0.06/kWh | $4.34 | $5.07 |
| Break-even electricity price | $0.110/kWh | $0.118/kWh |
Green marks the better value in a row (higher hashrate; lower power, J/TH, noise, weight, price and electricity cost). Specifications are as recorded for each product; “—” means the value is not stated. Economics are estimates at network conditions of 2026-10-28, $0.06/kWh, 2% pool fee and 100% uptime, and are not a forecast of earnings.
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