Load Average Calculator
Interpret a Linux load average number against the CPU core count to see if the system is healthy, fully loaded or overloaded.
Inputs
The 1, 5 or 15-minute load average from uptime/top
Load per Core
1.125
Effective Utilization
112.50%
Status
Overloaded — processes are queuing for CPU time
Spare Capacity (cores)
0.000
Step by step
Values used
Load Average = 4.50; CPU Cores = 4
Per-core load
per_core_load = load_average / cpu_cores
Load per Core
= 1.125
Effective Utilization
= 112.50
Status
= Overloaded — processes are queuing for CPU time
Spare Capacity (cores)
= 0.000
How it works
Linux load average approximates the number of processes that are running or waiting for CPU (and, historically, for uninterruptible I/O). It is only meaningful relative to the number of CPU cores: a load of 4 is idle on a 32-core server but is a warning sign of saturation on a 2-core one. Dividing load by core count gives a normalized per-core load, where 1.0 means the system is exactly saturated.
Formula
Per-core load
per_core_load = load_average / cpu_cores
- L
- reported load average
- n
- number of CPU cores
Frequently Asked Questions
What load average is considered healthy?
A commonly cited rule of thumb is that load average should stay below the number of CPU cores; many operators target roughly 70% of core count as a comfortable ceiling with headroom for spikes.
Why does load average include processes waiting on I/O?
Linux counts a process in the load average if it is running, runnable and waiting for CPU, or in an uninterruptible sleep state (usually waiting on disk I/O) — this is different from purely CPU-bound load metrics on some other Unix systems.
Which load average number should I watch — 1, 5 or 15 minute?
The 1-minute average reacts fastest to spikes but is noisy; the 15-minute average smooths out transient bursts and is a better signal of a sustained capacity problem. Many alerting setups watch all three together.