RAM Latency Calculator
Calculate memory latency from data rate and CAS latency
Calculate RAM Latency
Memory transfer rate in megatransfers per second
Column Address Strobe latency in clock cycles
Select your RAM generation for reference
RAM Latency Results
Calculation Details
Formula: RAM Latency = (CAS Latency × 2000) / Data Rate
Calculation: (16 × 2000) / 3200 = 10.00 ns
Memory Type: DDR4
Base Frequency: 1600 MHz (DDR doubles the effective rate)
Performance Analysis
Memory Module Decoder
Example: DDR4-3200 CL16
DDR4: Memory type/generation
3200: Data rate (3200 MT/s)
CL16: CAS Latency (16 cycles)
Latency: 16 × 2000 ÷ 3200 = 10 ns
Complete Module Label
16GB DDR4-3600 CL18-22-22-42
16GB: Module capacity
DDR4-3600: Type and speed
CL18: CAS Latency
22-22-42: Other timings (tRCD-tRP-tRAS)
Latency Performance Guide
RAM Tips
Lower latency = better performance
Higher frequency can offset higher CAS latency
Balance speed and latency for best value
Check motherboard compatibility first
Understanding RAM Latency
What is RAM Latency?
RAM latency is the delay before your memory can start processing CPU data, measured in nanoseconds. It represents the time it takes for your RAM to respond to a data request from the processor. Lower latency means faster response times and better performance.
Key Factors
- •Data Rate (MT/s): Memory transfer speed
- •CAS Latency (CL): Clock cycles to access data
- •Memory Type: DDR generation affects capabilities
Calculation Formula
RAM Latency = (CAS Latency × 2000) / Data Rate
Result in nanoseconds (ns)
Example: DDR4-3200 CL16
Latency = (16 × 2000) / 3200 = 10 ns
Note: The constant 2000 comes from converting MT/s to MHz and accounting for the clock cycle time calculation.
Memory Types and Typical Latencies
DDR3
• Typical: 13-15 ns
• Speed: 800-2133 MT/s
• Legacy standard
DDR4
• Typical: 10-15 ns
• Speed: 1600-4000+ MT/s
• Current mainstream
DDR5
• Typical: 12-18 ns
• Speed: 3200-8000+ MT/s
• Latest standard