GPU Hash Rate & Bandwidth Calculator
Estimate the mining performance of your graphics card based on hardware specifications.
GDDR5 (DDR)
GDDR6 (QDR)
GDDR6X (PAM4)
HBM/HBM2
Ethash / Etchash (Efficient)
KawPow (Moderate)
Autolykos2 (High Inten.)
Heavy Core Algos
Theoretical Memory Bandwidth:
0 GB/s
Estimated Hash Rate:
0 MH/s
*Note: Real-world results vary based on L3 cache (Infinity Cache), silicon lottery, and thermal throttling.
How to Calculate GPU Hash Rate
Calculating the hash rate of a GPU involves understanding the relationship between memory bandwidth and the specific mining algorithm's requirements. Most modern mining algorithms (like Ethash) are "memory-hard," meaning the speed at which the GPU can move data in and out of its VRAM is the primary bottleneck for performance.
The Core Formula for Memory Bandwidth
Before you can estimate the hash rate, you must find the Memory Bandwidth. This is the maximum rate at which data can be read from or stored into the VRAM by the GPU core.
Bandwidth Formula:
Bandwidth (GB/s) = (Effective Memory Clock × Bus Width) / 8 / 1000
Bandwidth (GB/s) = (Effective Memory Clock × Bus Width) / 8 / 1000
Step-by-Step Calculation Guide
- Find the Clock Speed: Check your GPU specs (e.g., 1750 MHz).
- Determine the Multiplier: GDDR6 has a 4x multiplier (Command/Address), while GDDR6X uses PAM4 signaling for even higher effective speeds.
- Identify Bus Width: Usually ranges from 128-bit (entry level) to 384-bit (high end).
- Calculate Bandwidth: Multiply these values and divide by 8 to convert bits to bytes.
- Apply Algorithm Factor: Different algorithms convert bandwidth to hashes differently. For Ethash, the ratio is typically 0.22 to 0.28.
Example: Calculating an RTX 3080
Let's look at a realistic example for an NVIDIA RTX 3080:
- Memory Clock: 1188 MHz (Base)
- Memory Type: GDDR6X (Multiplier effect results in ~19,000 MHz effective)
- Bus Width: 320-bit
Calculated Bandwidth: 760 GB/s. When applying the Ethash efficiency factor, this results in the well-known ~95-100 MH/s hash rate seen in optimized mining rigs.
Why doesn't my calculated hash rate match my miner?
There are several factors that can lead to discrepancies:
- Silicon Lottery: Some chips can handle higher overclocks than others.
- LHR (Low Hash Rate): Some NVIDIA cards have hardware/firmware limiters specifically designed to reduce mining performance.
- Thermal Throttling: GDDR6X memory runs very hot; if it exceeds 100°C, the card will automatically slow down to protect itself.
- Miner Software: Different software (PhoenixMiner, Gminer, T-Rex) has different optimization levels for specific kernels.