RAM Latency Calculator
Calculate real memory latency in nanoseconds from your RAM specs
RAM Specifications
Results
Popular RAM Configurations
| Config | Speed | CL | Latency (ns) | Bandwidth | Rating |
|---|---|---|---|---|---|
| DDR4-2666 CL19 | 2666 MHz | 19 | 14.3 ns | 42.7 GB/s | High |
| DDR4-3200 CL16 | 3200 MHz | 16 | 10.0 ns | 51.2 GB/s | Great |
| DDR4-3200 CL22 | 3200 MHz | 22 | 13.8 ns | 51.2 GB/s | High |
| DDR4-3600 CL16 | 3600 MHz | 16 | 8.9 ns | 57.6 GB/s | Excellent |
| DDR4-3600 CL18 | 3600 MHz | 18 | 10.0 ns | 57.6 GB/s | Great |
| DDR4-4000 CL18 | 4000 MHz | 18 | 9.0 ns | 64.0 GB/s | Excellent |
| DDR5-4800 CL40 | 4800 MHz | 40 | 16.7 ns | 76.8 GB/s | High |
| DDR5-5600 CL36 | 5600 MHz | 36 | 12.9 ns | 89.6 GB/s | Good |
| DDR5-5600 CL46 | 5600 MHz | 46 | 16.4 ns | 89.6 GB/s | High |
| DDR5-6000 CL30 | 6000 MHz | 30 | 10.0 ns | 96.0 GB/s | Great |
| DDR5-6400 CL32 | 6400 MHz | 32 | 10.0 ns | 102.4 GB/s | Great |
| DDR5-7200 CL34 | 7200 MHz | 34 | 9.4 ns | 115.2 GB/s | Excellent |
What is Real RAM Latency?
The CAS latency number (e.g. CL16) is measured in clock cycles, not time. To find the actual time delay your CPU waits for memory access, you need to convert it to nanoseconds using the memory clock speed.
The formula is: Real Latency (ns) = (CL × 2000) ÷ Speed (MHz)
This means a 3200 MHz CL16 kit and a 3600 MHz CL18 kit both result in exactly 10 ns latency — the faster speed compensates for the higher CL number.
Latency Tiers for Gaming
≤ 9.5 ns — Excellent: Ideal for competitive gaming. Reduces frame time variance and input lag.
9.5–11 ns — Great: Excellent performance for all gaming scenarios.
11–13 ns — Good: Solid for casual gaming. Marginal impact in most titles.
> 13 ns — Poor: May cause stutters or frame time inconsistencies in fast-paced games.
DDR4 vs DDR5 Latency
DDR5 kits often have much higher CL numbers (e.g. CL40) than DDR4, but their higher MHz speeds keep real latency competitive. A DDR5-6000 CL30 kit delivers ~10 ns — the same as DDR4-3200 CL16. Always use this calculator to compare kits by their real latency, not just the CL number.