Antminer S21+
Enhanced S21 with improved BM1370 chips. 216 TH/s at 16.5 J/TH efficiency. Standard Antminer form factor.
Professional-Grade Miner
This miner draws 3,564W and produces 75 dB of noise — it is designed for dedicated mining environments, not living spaces. Professional-grade miners deliver the highest hashrate and revenue per unit but require proper infrastructure: a 240V circuit, adequate ventilation or exhaust ducting, and a space where noise is not a concern (garage, basement, warehouse, or outdoor enclosure).
For home miners looking for a quieter alternative, consider our Bitcoin Space Heater builds or explore open-source miners like the Bitaxe that are purpose-built for residential environments.
Profitability Calculator
| Period | Revenue | Electricity Cost | Profit |
|---|---|---|---|
| Daily | $5.95 | $5.99 | $-0.04 |
| Weekly | $41.66 | $41.91 | $-0.25 |
| Monthly | $178.54 | $179.63 | $-1.09 |
| Yearly | $2,172.23 | $2,185.44 | $-13.21 |
Heating offset estimates the value of heat replacing an electric space heater during heating season (~6 months/year in Canada). Actual savings depend on your heating setup and climate.
Where to Buy the Antminer S21+
D-Central Technologies
CanadaBitcoin Mining Hackers since 2016. Ships from Laval, Quebec.
Shop all Bitcoin mining productsASIC Miner Market
United StatesWide selection of new and used ASIC miners. US-based shipping.
Shop NowFull Specifications
| Model | Antminer S21+ |
| Model Number | S21+ |
| Manufacturer | Bitmain |
| Algorithm | SHA-256 |
| Coins Mined | Bitcoin (BTC) |
| Hashrate | 216 TH/s |
| Power Consumption | 3,564 W |
| Efficiency | 16.5 J/TH |
| Noise Level | 75 dB |
| Chip Model | BM1370 |
| Cooling | Air |
| Voltage Range | 200-240V AC |
| Operating Temperature | 5-40°C |
| Dimensions | 400x195x290 |
| Weight | 15 |
| Interface | Ethernet |
| BTU Output | 12160.4 BTU/hr |
| Equivalent Heater | Equal to a 3,564W space heater |
| Daily Power Cost | $5.99/day |
| Monthly Power Cost | $179.63/mo |
| Circuit Requirement | 240V circuit required |
| Release Date | 2025-01-01 |
| MSRP | $6,500.00 |
| Status | Active |
Custom Power Profiles
With custom firmware like DCENT_OS, this miner can be tuned across a wide range of power levels. Lower wattage improves efficiency and reduces electricity costs; higher wattage increases hashrate at the expense of efficiency.
Normal Mode
| Wattage | Hashrate | Efficiency |
|---|---|---|
| 2,640 W | 176 TH/s | 15 J/TH |
| 2,890 W | 194 TH/s | 14.9 J/TH |
| 3,160 W | 212 TH/s | 14.9 J/TH |
| 3,430 W | 230 TH/s | 14.9 J/TH |
| 3,700 W | 248 TH/s | 14.9 J/TH |
| 3,970 W | 266 TH/s | 14.9 J/TH |
| 4,240 W | 283 TH/s | 15 J/TH |
| 4,510 W | 301 TH/s | 15 J/TH |
| 4,690 W | 313 TH/s | 15 J/TH |
Performance Mode
| Wattage | Hashrate | Efficiency |
|---|---|---|
| 3,975 W | 265 TH/s | 15 J/TH |
| 4,365 W | 291 TH/s | 15 J/TH |
| 4,755 W | 317 TH/s | 15 J/TH |
| 5,145 W | 343 TH/s | 15 J/TH |
| 5,535 W | 369 TH/s | 15 J/TH |
| 5,940 W | 396 TH/s | 15 J/TH |
| 6,382 W | 413 TH/s | 15.5 J/TH |
| 6,845 W | 430 TH/s | 15.9 J/TH |
| 7,347 W | 448 TH/s | 16.4 J/TH |
Low Power Mode
| Wattage | Hashrate | Efficiency |
|---|---|---|
| 2,440 W | 170 TH/s | 14.4 J/TH |
| 2,500 W | 176 TH/s | 14.2 J/TH |
| 2,680 W | 188 TH/s | 14.3 J/TH |
| 2,830 W | 200 TH/s | 14.2 J/TH |
| 2,910 W | 206 TH/s | 14.1 J/TH |
| 3,130 W | 218 TH/s | 14.4 J/TH |
| 3,320 W | 230 TH/s | 14.4 J/TH |
| 3,550 W | 242 TH/s | 14.7 J/TH |
| 3,650 W | 248 TH/s | 14.7 J/TH |
Actual performance varies by individual unit silicon quality, ambient temperature, and cooling configuration. These operating points are achievable with custom tuning firmware such as DCENT_OS; values are calculated at runtime by the autotuner, not fixed presets.
Home Mining Assessment
Enhanced S21 with improved BM1370 chips. 216 TH/s at 16.5 J/TH efficiency. Standard Antminer form factor.
The Antminer S21+ is a SHA-256 cryptocurrency miner manufactured by Bitmain. It delivers a hashrate of 216 TH/s with a power consumption of 3564W, achieving an efficiency of 16.5 J/TH.
Built on the BM1370 ASIC chip, uses air cooling, operates at 75 dB noise level, weighs 15 kg, measures 400x195x290.
With a home mining score of 30/100, this miner is best suited for dedicated mining spaces for residential use. It produces 12160.4 BTU/h of heat output, making it effective for supplemental space heating.
At 16.5 J/TH, the Antminer S21+ sits in the current-generation efficiency tier, competitive with modern SHA-256 hardware (roughly 13-19 J/TH).
Its waste heat (around 12160.4 BTU/h) can be ducted into a room, turning money you would otherwise spend on heating into hashrate.
D-Central’s in-house technicians repair the Antminer S21+.
View detailed specifications, real-time profitability calculations, and comparison data for the Antminer S21+ in our comprehensive ASIC miner database.
Antminer S21 specs, repair, and parts
Use the S21 cluster to connect current-generation specs, buying options, chip-level parts, troubleshooting, and repair support.
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Frequently Asked Questions
What are the current mining economics for the Antminer S21+?
At $0.07/kWh, the Antminer S21+ currently shows an estimated daily net cost of $0.04 before pool fees and hardware cost. Lower electricity rates, network changes, BTC price changes, or useful heat recovery can change the result.
Can I mine Bitcoin at home with the Antminer S21+?
The Antminer S21+ has a home mining score of 30/100. With 75 dB noise and 3,564W power draw, it may require a dedicated space like a garage, basement, or outdoor enclosure. Consider noise insulation and proper ventilation.
Can the Antminer S21+ heat my home?
The Antminer S21+ outputs approximately 12160.4 BTU/hr of heat. For reference, a typical space heater produces 5,000-5,500 BTU/hr. All electrical energy consumed by the miner is converted to heat, making it 100% efficient as a heater. D-Central offers Bitcoin Space Heater builds designed specifically for home heating integration.
Does D-Central repair the Antminer S21+?
Yes, D-Central provides professional repair services for the Antminer S21+. Services include hashboard repair, control board diagnostics, fan replacement, and full refurbishment. Ship your miner to our Laval, Quebec facility for diagnosis and repair.
What power supply does the Antminer S21+ need?
The Antminer S21+ draws 3,564W of power. You need a power supply rated for at least 3,920W with appropriate voltage (200-240V AC). D-Central stocks compatible power supplies in our shop. Always use a quality PSU from a reputable manufacturer to protect the miner and wiring.