CPU Benchmark Converter
Estimate approximate FLOPS performance from CPU clock speed, core count, and operations per cycle.
Compare theoretical vs real-world performance.
Enter CPU specs to estimate theoretical FLOPS, or convert between FLOPS scales.
Understanding CPU Performance Metrics
CPU performance is often described in terms of clock speed (GHz) and floating-point operations per second (FLOPS). However, converting between these is not a simple direct conversion because modern processors can perform multiple operations per clock cycle, and real-world performance depends on many factors including instruction pipelining, cache efficiency, memory bandwidth, and workload characteristics.
Theoretical Peak FLOPS Formula:
FLOPS = Cores × Clock Speed (GHz) × Operations per Cycle × 10⁹
For modern CPUs, the operations per cycle depend on the instruction set:
- SSE (128-bit): 4 single-precision or 2 double-precision operations per cycle
- AVX2 (256-bit): 8 single-precision or 4 double-precision per cycle
- AVX-512 (512-bit): 16 single-precision or 8 double-precision per cycle
Most modern desktop CPUs support AVX2, so they can perform 8 single-precision floating-point operations per cycle per core (with FMA, this doubles to 16).
FLOPS Scale Reference:
| Prefix | Value | Example |
|---|---|---|
| MFLOPS (Mega) | 10⁶ | Early PCs (1980s-1990s) |
| GFLOPS (Giga) | 10⁹ | Single modern CPU core |
| TFLOPS (Tera) | 10¹² | Modern desktop CPU or GPU |
| PFLOPS (Peta) | 10¹⁵ | Supercomputers |
| EFLOPS (Exa) | 10¹⁸ | Frontier-class supercomputers |
Practical Examples:
- A 4-core CPU at 4.0 GHz with AVX2 (16 ops/cycle with FMA): 4 × 4.0 × 16 × 10⁹ = 256 GFLOPS theoretical peak (single precision).
- An 8-core CPU at 3.5 GHz with AVX2: 8 × 3.5 × 16 × 10⁹ = 448 GFLOPS theoretical peak.
- A 16-core server CPU at 2.5 GHz with AVX-512: 16 × 2.5 × 32 × 10⁹ = 1.28 TFLOPS theoretical peak.
Real-World vs Theoretical Performance:
Theoretical peak FLOPS is almost never achieved in real-world applications. Typical real-world efficiency ranges from 30-70% of theoretical peak depending on the workload:
- Highly optimized scientific computing: 50-70% efficiency
- General-purpose applications: 10-30% efficiency
- Memory-bound workloads: 5-15% efficiency
Clock Speed Units:
| Unit | Value |
|---|---|
| 1 MHz | 1,000,000 cycles per second |
| 1 GHz | 1,000 MHz = 1,000,000,000 cycles per second |
| 1 THz | 1,000 GHz (theoretical, not yet achieved in consumer CPUs) |
Tips:
- Clock speed alone is a poor indicator of CPU performance. A 3 GHz CPU with wide execution units can outperform a 5 GHz CPU with narrow ones.
- GPU FLOPS are typically much higher than CPU FLOPS because GPUs have thousands of simpler cores optimized for parallel workloads.
- When comparing CPUs, look at benchmark scores for your specific workload rather than relying on theoretical FLOPS calculations.
How we build and check this converter
This converter runs entirely in your browser, so the numbers you enter stay on your device. The math behind it is written by hand and tested against worked examples and standard references before the page goes live.
SuperGlobalCalculator is independently built and maintained. See how we build and verify our calculators.