Antminer K7 vs Antminer S9j
Side-by-side specs, profitability, and home mining comparison.
Specifications Comparison
| Antminer K7 | Specification | Antminer S9j |
|---|---|---|
| 63.5 TH/s | Hashrate | 14.5 TH/s |
| 3,080 W | Power Consumption | 1,350 W |
| 48.5 J/TH | Efficiency | 93.1 J/TH |
| 75 dB | Noise Level | 76 dB |
| 14.0 kg | Weight | 4.2 kg |
| 10,509 BTU/hr | BTU Output | 4,606 BTU/hr |
| 36/100 | Home Mining Score | 83/100 |
| — | Release Year | — |
| Eaglesong | Algorithm | SHA-256 |
| Bitmain | Manufacturer | Bitmain |
Profitability Comparison
Antminer K7
Antminer S9j
Based on BTC price of $79,087 and current network difficulty as of May 15, 2026. Actual results vary.
Verdict
Run the numbers across every spec and the Antminer K7 edges it: 3 of 5 factors go its way (efficiency, hashrate, noise level). The standout gap is 338% more hashrate (63.5 vs 14.5 TH/s) in the Antminer K7's favour. The Antminer S9j holds the edge in power consumption and home mining score. The right pick still depends on your power cost and noise tolerance — the breakdowns above make that call concrete.
Spec Deltas
Here is every spec where the Antminer K7 and Antminer S9j actually differ, with the gap quantified:
- Antminer K7 338% more hashrate (63.5 vs 14.5 TH/s)
- Antminer S9j 56% better power draw (3,080 vs 1,350 W)
- Antminer K7 48% better efficiency (48.5 vs 93.1 J/TH)
- Antminer K7 1% better noise (75.0 vs 76.0 dB)
- Antminer S9j 70% better weight (14.0 vs 4.2 kg)
- Antminer K7 128% more heat output (10,509 vs 4,606 BTU/hr)
- Antminer S9j 131% more home mining score (36.0 vs 83.0)
Cost & ROI Over Time
Sticker price versus what the miner actually earns back: the table below projects cumulative net profit at a $0.10/kWh electricity rate.
| Antminer K7 | Metric | Antminer S9j |
|---|---|---|
| $3,500 | Upfront cost (MSRP) | — |
| -$5.01 | Daily net profit | -$2.70 |
| -$5,328 | Net after 1 year | -$984 |
| -$7,156 | Net after 2 years | -$1,968 |
| -$8,985 | Net after 3 years | -$2,952 |
| Does not pay back at current rates (negative daily profit) | Payback period | — |
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
TieBoth miners produce similar daily profit.
Best for Home Mining
Antminer S9jScore: 83/100. 76 dB noise level.
Best for Efficiency
Antminer K748.5 J/TH — lower electricity cost per terahash.
Frequently Asked Questions
Antminer K7 vs Antminer S9j: which one earns more per day?
At the current BTC price and a $0.10/kWh electricity rate, the Antminer S9j is more profitable at $-2.70/day compared to $-5.01/day for the Antminer K7. Profitability depends heavily on your electricity rate — use the selector above to calculate with your actual costs.
Which is quieter, the Antminer K7 or Antminer S9j?
The Antminer K7 is quieter at 75 dB compared to the Antminer S9j at 76 dB. For home mining, lower noise levels make a significant difference in livability.
Antminer K7 vs Antminer S9j: which fits a residential setup better?
The Antminer S9j scores 83/100 on our Home Mining Score (vs 36/100 for the Antminer K7). This composite score factors in noise, power requirements, heat output, size, and setup ease — all critical for residential mining.
What is the efficiency difference between Antminer K7 and Antminer S9j?
The Antminer K7 runs at 48.5 J/TH while the Antminer S9j runs at 93.1 J/TH — a difference of 44.6 J/TH. Lower efficiency means less electricity per terahash of mining power, directly reducing operating costs. In relative terms that is 48% better efficiency (48.5 vs 93.1 J/TH).