ASIC Profitability Calculator: Methodology and Ready-Made Scenarios for S21

Mining requires accurate calculations before launching a farm. Even the most modern ASIC can be unprofitable if the tariff is incorrect or the pool commissions are high. This is where Vnish’s ASIC profitability calculator comes in handy. This calculator is designed to quickly check the profitability of mining. The user only needs to enter three parameters: equipment hashrate (TH/s), power consumption (W) and electricity tariff (USD/kWh). After pressing the Calculate button, the system instantly displays the projected daily profit.

This tool allows you to estimate the basic profitability of any ASIC in a matter of seconds. However, in order for the calculation to be as accurate as possible and reflect real conditions, additional information must be taken into account: network complexity, pool commissions, hash price changes, cooling costs and equipment efficiency. Taking these nuances into account will help you see the full picture and avoid errors when planning your return on investment.

Profitability calculator from Vnish: enter the hashrate, energy consumption and tariff to calculate the profitability of mining.

Method used

The methodology for assessing mining profitability is based on a combination of equipment specifications and external market variables. The purpose of this approach is to determine how much net profit a miner generates under specific conditions and how long it will take to recoup the investment.
Basic variables:

1. Hash rate (TH/s)
   The power of the device, which determines the number of calculations per second. The higher it is, the more chances there are to receive a reward. For more information on what hashrate is and how to measure it correctly, read the special article.
2. Power consumption (W)
   Shows how much electricity the device consumes to achieve the specified hashrate.
3. Electricity cost (USD/kWh)
   One of the most important factors. In many farms, electricity costs account for 50-70% of all operating costs.
4. Pool commissions (%)
   Depending on the payment model (FPPS, PPS+, PPLNS), net income may decrease by 1–3% or more.
5. BTC price and network difficulty
   The price of the coin determines the final income in dollars, and the difficulty regulates the frequency of finding blocks. These two factors are constantly changing and create cyclical profitability.

Basic principles

• Accuracy depends on the relevance of the data: the BTC rate, complexity, and hash price need to be updated regularly.
• Energy efficiency determines ROI: a reduction in W/TH by even 5-10% reduces the payback period by several months.
• Pool rewards affect income stability: FPPS and PPS+ are suitable for predictable income, PPLNS is for those who are ready for volatility.
• Scenario planning is a must: miners should check both optimistic and pessimistic scenarios changes in BTC price, tariffs, and difficulty.

This approach allows you to make a realistic profitability forecast before launching the equipment and make an informed investment decision.

Scenarios by model & tariff

Let’s consider the Antminer S21 model in its standard configuration: 200 TH/s with a consumption of about 3500 W, which corresponds to an efficiency of ~17.5 W/TH. The device is capable of operating profitably even in regions with average tariffs, but the final result directly depends on the cost of electricity.

Daily cost of electricity

For calculation: 3.5 kW × 24 hours = 84 kWh per day:

• Tariff $0.05/kW·h: 84 × 0.05 = $4.20
• Tariff $0.06/kW·h: 84 × 0.06 = $5.04
• Tariff $0.08/kW·h: 84 × 0.08 = $6.72

Net profit

Formula:
Net profit = (Hash price × 200 TH) – Electricity costs – Pool commission

Let’s assume that the average hash price is $0.06/TH/day:

• Gross income: 200 × 0.06 = $12.00/day
• Pool commission 2%: $0.24

Result for three rates:

• $0.05 tariff: 12.00 – 4.20 – 0.24 = $7.56/day
• $0.06 rate: 12.00 – 5.04 – 0.24 = $6.72/day
• $0.08 tariff: 12.00 – 6.72 – 0.24 = $5.04/day

W/TH optimisation

Reducing consumption from 17.5 W/TH to 15 W/TH lowers power from 3500 W to 3000 W. This means 72 kWh instead of 84 kWh per day, i.e. a saving of 12 kWh every day. At a rate of $0.06, this optimisation saves about $0.72 per day per device, or over $700 per month for a farm with 100 machines. This effect directly reduces the payback period and increases ROI even without changing the hashrate.

Table with examples of popular Antminer models: hashrate, power consumption and daily profit.

What to change for your farm

Optimising a mining farm does not always mean buying new machines. Often, proper management of what is already installed can have a much greater effect. Every change in settings or operating conditions can significantly affect the final result: reduce payback period, increase ROI, and reduce downtime risks.

Where to start

1. Check the average electricity rate in your region. Even a difference of £0.01/kWh can change your profitability by hundreds of pounds per month.
2. Compare several miner models in the profitability calculator. This will help you determine how much more efficient modern devices are compared to older ones.
3. Assess the feasibility of replacing equipment. Sometimes it is better to upgrade your current farm (firmware, cooling) than to invest in new ASICs.

Additional factors

• Choose a pool with lower fees. A fee of 1–2% seems insignificant, but with large volumes, it eats away at a significant portion of your profits.
• Use custom firmware to reduce W/TH. Optimised settings can reduce power consumption by 5–10% without losing hashrate stability.
• Scale only after profitability tests. It is worth testing several machines in new conditions first, and only then scaling the changes to the entire farm.

Thus, competent optimisation consists of a comprehensive approach: not only monitoring equipment, but also regularly analysing tariffs, pool conditions and the effectiveness of settings. This allows you to increase profitability even without new investments in equipment.

Case: how lower W/TH shifts ROI

The use of custom firmware opens up new opportunities for miners that go beyond the standard functionality of stock software. While factory firmware provides only basic settings, an optimised solution allows for better control of equipment, reduced energy consumption, and stabilised chip operation. As a result, the farm owner receives more predictable income and lower operating costs.

The table shows the key differences between stock and custom Vnish firmware, highlighting the benefits of optimisation for energy efficiency, stability, and large farm management.

Thus, custom firmware provides a significant advantage in scaling: it not only increases the efficiency of each individual ASIC, but also simplifies the centralised management of hundreds of devices, making the farm more stable and profitable in the long term. To increase equipment efficiency and reduce electricity costs, you can download the latest firmware versions from the official Vnish website.

Conclusions

Mining always depends on many variables, and correct calculations help to avoid unnecessary risks. We have looked at how profitability is affected by basic equipment parameters, electricity tariffs, pool fees and market factors. It has been shown that even a small reduction in energy consumption or a difference in the cost per kilowatt-hour can significantly reduce or, conversely, extend the payback period.

It was also emphasised that in order to increase efficiency, it is worth paying attention not only to the purchase of new equipment, but also to the optimisation of existing equipment  through the right choice of pool, configuration and use of custom firmware. This allows you to make the farm’s operation more stable, reduce costs and increase the predictability of results.

Ultimately, mining profitability is determined not by a single factor, but by a combination of technical and economic decisions. Those who take all the nuances into account and constantly check their scenarios will gain a competitive advantage and more stable income in the long term.