When working on performance optimization or system monitoring, knowing your Mac's hardware specs is essential. Here are the most efficient terminal commands:


To get the number of physical CPU cores:
sysctl -n hw.physicalcpu

For logical processors (including hyper-threading):
sysctl -n hw.logicalcpu

To get detailed CPU architecture information:
sysctl -n machdep.cpu.brand_string


For total installed RAM in bytes:
sysctl -n hw.memsize

Convert to human-readable GB format:
echo $(( $(sysctl -n hw.memsize) / 1073741824 )) GB


For a more comprehensive hardware report:
system_profiler SPHardwareDataType

Sample output (truncated):

Hardware Overview:
  Model Name: MacBook Pro
  Model Identifier: MacBookPro18,3
  Chip: Apple M1 Pro
  Total Number of Cores: 10 (8 performance and 2 efficiency)
  Memory: 32 GB



Create this function in your .bash_profile for quick checks:

function sysinfo() {
  echo "CPU: $(sysctl -n machdep.cpu.brand_string)"
  echo "Cores: $(sysctl -n hw.physicalcpu) physical, $(sysctl -n hw.logicalcpu) logical"
  echo "RAM: $(( $(sysctl -n hw.memsize) / 1073741824 )) GB"
}



For scripting purposes, here's how to extract just the memory value:

system_profiler SPHardwareDataType | awk '/Memory/ {print $2,$3}'



These commands execute differently:

sysctl - Instant (~0.001s)
system_profiler - Slower (~1-2s) but more detailed

When developing performance-sensitive applications or troubleshooting system issues, knowing your hardware specs is crucial. Here are the most efficient terminal commands for macOS:

sysctl -n hw.ncpu
# Returns just the number of active CPU cores
# Example output: 8

For more detailed CPU architecture information:

sysctl -n machdep.cpu.brand_string
# Example output: Intel(R) Core(TM) i7-9750H CPU @ 2.60GHz

sysctl -n hw.memsize
# Returns RAM in bytes (divide by bytes for GB)
# Example output: 17179869184 (16GB)

For human-readable output:

system_profiler SPHardwareDataType | grep "Memory"
# Example output: Memory: 16 GB

Create an alias for quick system checks:

alias sysinfo='echo "CPU Cores: $(sysctl -n hw.ncpu)" & echo "RAM: $(($(sysctl -n hw.memsize)/1024/1024/1024)) GB"'
# Usage: sysinfo
# Example output:
# CPU Cores: 8
# RAM: 16 GB

For developers needing more detailed hardware information:

system_profiler SPHardwareDataType
# Provides comprehensive hardware report including:
# - Processor details
# - Memory configuration
# - Serial numbers
# - Boot ROM version

For script-friendly JSON output (macOS 10.10+):

system_profiler SPHardwareDataType -json
# Returns machine-readable JSON format

These commands are particularly useful for:

• Build system configuration scripts
• Docker container resource allocation
• Performance benchmarking tools
• System requirement validation

Remember that virtualized environments might report different values than physical hardware.