Bitcoin ASIC Specs Explained: TH/s, Watts, J/TH, Price

Hashrate (TH/s)

Hashrate is the number of SHA-256 hashes a machine can compute per second. It's the number-one mining metric: higher hashrate, bigger proportional slice of pool rewards.

The 2026 standard unit is the terahash per second (TH/s): 1 TH/s = 10¹² hashes per second = one trillion. Current machines range from 100 TH/s (legacy entry) to 580 TH/s (hydro flagship).

A few benchmarks:

• Antminer S19j Pro+: 122 TH/s
• Whatsminer M60S: 172 TH/s
• Antminer S21 Pro: 234 TH/s
• Antminer S21 XP Hyd: 473 TH/s
• Antminer S23 Hydro 3U: 580 TH/s

Doubling hashrate in an equivalent machine doubles your theoretical revenue — all else equal. But it also means more watts and a higher purchase price. Hence the importance of the next two specs.

Power (W)

Power is wall-plug draw: what your electricity meter records when the machine runs. Expressed in watts (W) or kilowatts (kW).

A modern machine draws between 1,800 W (entry-tier) and 5,500 W (hydro flagship). Continuously. Over a month (730 hours):

• 1,800 W → 1,314 kWh/month → $85 at $0.065/kWh
• 3,850 W → 2,810 kWh/month → $183 at $0.065/kWh
• 5,500 W → 4,015 kWh/month → $261 at $0.065/kWh

At US residential rates ($0.16/kWh), multiply by 2.5×. This is why home mining is almost always loss-making outside very cheap utility markets — see Hosted Bitcoin Mining.

Note: the "power" spec advertised by manufacturers is typically nominal; in practice wall-draw can vary by ±5% depending on temperature, PSU efficiency, and firmware. To compare machines, always divide power by hashrate.

Efficiency (J/TH)

Efficiency is the power/hashrate ratio, expressed in joules per terahash (J/TH). It's the metric that predicts mid-term profitability.

Lower J/TH = better: fewer watts consumed per hash produced, so more margin against electricity.

2026 benchmarks:

• 9–12 J/TH: hydro flagship (S23 Hydro 3U at 9.5 J/TH, S21 XP Hyd at 12.0 J/TH)
• 13–17 J/TH: mainstream air (S21 Pro at 16.5 J/TH, S21 at 17.5 J/TH)
• 18–25 J/TH: entry air (M60S at 18.8 J/TH, S19j Pro+ at 27.5 J/TH)
• >25 J/TH: legacy machines, economically obsolete unless electricity < $0.045/kWh

Why it's central: at hashprice $50/PH/day (2026 benchmark), a 16 J/TH machine generates ~$0.12/day per raw TH. At $0.065/kWh, the electricity cost is ~$0.025/day per TH. Gross margin: ~$0.095/day per TH. On 234 TH/s × 365 days = $8,100/year.

But at 30 J/TH? Electricity cost doubles, margin falls to ~$0.07/TH, payback blows out. That's the whole efficiency game.

Price and payback

Price is expressed in dollars per terahash ($/TH) — the yardstick that lets you compare machines of different sizes.

Calculation: machine price ($) ÷ hashrate (TH/s).

2026 benchmarks:

• Under $35/TH: excellent deal (rare outside used market or fire sales)
• $35–50/TH: decent on recent new gear
• $50–70/TH: standard market price
• $70+/TH: overpriced unless efficiency is exceptional (< 12 J/TH)

Concrete example: an S21 Pro at $6,000 / 234 TH = $25.6/TH. Very good. A new S19j Pro+ at $3,250 / 122 TH = $26.6/TH — but at 27 J/TH efficiency, the operational cost catches up fast.

Payback (months to recover the investment) depends on hashprice, your electricity rate, and hosting cost. See Bitcoin Mining Profitability 2026 for the detailed math.

Bonus: noise, dimensions, cooling

Three specs often overlooked but frequently decisive for deployment.

Noise. An air-cooled machine produces 70–80 dB(A) at full load. Equivalent to a continuous lawn mower. Forbidden in any residential setting unless heavily soundproofed (insulated shed, basement). Hydro machines drop to 45–55 dB(A) — quieter but require a cooling loop.

Dimensions and weight. A standard ASIC is roughly 400 × 200 × 300 mm and 14 kg. A 3U hydro unit (e.g. S23) is larger and longer. Matters for hosting rack compatibility (19" standard).

Cooling type. Three options:

• Air: integrated fans, simplest deployment, the volume standard.
• Hydro: cold plate + water loop, quieter and more efficient, but dedicated infra required.
• Immersion: machine submerged in dielectric fluid, highest performance but heavy to deploy.

Cooling type determines hosting site choice. See Bitcoin ASIC guide "How to start" section.

Disclaimer: Bitcoin mining carries a risk of capital loss. Numbers above are 2026 references and evolve with hashprice and each new hardware generation.