To check how much RAM you have on Windows, open Settings > System > About and read “Installed RAM”; on a Mac, click the Apple menu > About This Mac and read “Memory”. Both take about ten seconds and work on any laptop.
Windows: Settings and Task Manager
Settings (quickest): 1. Press Windows + I. 2. Go to System > About. 3. Look at Installed RAM under Device specifications, for example “8.00 GB (7.79 GB usable)”.
Task Manager (more detail): 1. Press Ctrl + Shift + Esc. 2. Open the Performance tab and click Memory. 3. The total is at the top right. Below the graph you’ll see Speed, Slots used (for example “1 of 2”) and Form factor.
“Slots used: 1 of 2” means there’s a free slot, so adding RAM is usually easy. “2 of 2” means you’d replace sticks to upgrade. If no slots are listed, the RAM may be soldered to the board.
Mac: About This Mac
- Click the Apple menu at the top left.
- Choose About This Mac.
- Read Memory, for example “16 GB”.
On Apple silicon Macs (M1 and later) the memory is part of the chip and can never be upgraded. Many older Intel Macs can’t be upgraded either, so buy the amount you’ll need.
How much RAM your laptop can take
The maximum depends on the processor and the motherboard:
- Search the exact model number (on the sticker underneath or in System > About) with “maximum memory” or “specifications” on the maker’s support site. Dell, HP and Lenovo list it per model.
- Check Windows’ own figure: open PowerShell and run
Get-CimInstance Win32_PhysicalMemoryArray | Select MaxCapacityEx, MemoryDevicesMemoryDevices is the number of slots; MaxCapacityEx is the firmware’s limit in kilobytes (divide by 1,048,576 for GB). A 0 means it isn’t reported. - Thin laptops often have soldered RAM or one slot only. Check before buying sticks.
This matters when you’re checking an ex-UK laptop before paying: confirm the RAM matches what the seller said and see whether a slot is free. Our 15-minute used laptop test covers the rest.
Free vs installed RAM
- Installed is the total fitted in the laptop.
- Usable is a little lower because some is reserved, often for built-in graphics.
- In use / Available in Task Manager changes all the time. Windows fills spare RAM with cache, which is normal.
If memory is near 90% in use most of the day, you’ll feel it as slowness. See how much RAM you need before upgrading.
Quick answers
Windows: Settings > System > About > Installed RAM. Mac: Apple menu > About This Mac > Memory.
Look up the exact model’s specifications on the maker’s site, or check MaxCapacityEx in PowerShell. Soldered RAM and Apple silicon Macs can’t be upgraded.
