Antminer S21+ vs Antminer S9i
Side-by-side specs, profitability, and home mining comparison.
Specifications Comparison
| Antminer S21+ | Specification | Antminer S9i |
|---|---|---|
| 216.0 TH/s | Hashrate | 14.0 TH/s |
| 3,564 W | Power Consumption | 1,320 W |
| 16.5 J/TH | Efficiency | 94.3 J/TH |
| 75 dB | Noise Level | 76 dB |
| 15.0 kg | Weight | 4.2 kg |
| 12,160 BTU/hr | BTU Output | 4,504 BTU/hr |
| 30/100 | Home Mining Score | 83/100 |
| — | Release Year | — |
| SHA-256 | Algorithm | SHA-256 |
| Bitmain | Manufacturer | Bitmain |
Profitability Comparison
Antminer S21+
Antminer S9i
Based on BTC price of $78,041 and current network difficulty as of Apr 26, 2026. Actual results vary.
Verdict
Based on our multi-factor analysis, the Antminer S21+ wins on 3 of 5 factors (efficiency, hashrate, noise level). The Antminer S9i holds the edge in power consumption and home mining score. Review the detailed specs and profitability calculations above to determine which miner best fits your specific setup.
Best For...
Best for Profitability
TieBoth miners produce similar daily profit.
Best for Home Mining
Antminer S9iScore: 83/100. 76 dB noise level.
Best for Efficiency
Antminer S21+16.5 J/TH — lower electricity cost per terahash.
Frequently Asked Questions
Is the Antminer S21+ or Antminer S9i more profitable?
At the current BTC price and a $0.10/kWh electricity rate, the Antminer S21+ is more profitable at $-0.74/day compared to $-2.66/day for the Antminer S9i. Profitability depends heavily on your electricity rate — use the selector above to calculate with your actual costs.
Which is quieter, the Antminer S21+ or Antminer S9i?
The Antminer S21+ is quieter at 75 dB compared to the Antminer S9i at 76 dB. For home mining, lower noise levels make a significant difference in livability.
Which is better for home mining, the Antminer S21+ or Antminer S9i?
The Antminer S9i scores 83/100 on our Home Mining Score (vs 30/100 for the Antminer S21+). 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 S21+ and Antminer S9i?
The Antminer S21+ runs at 16.5 J/TH while the Antminer S9i runs at 94.3 J/TH — a difference of 77.8 J/TH. Lower efficiency means less electricity per terahash of mining power, directly reducing operating costs.