VA vs Watts: The Two Numbers on a UPS, Explained
Last verified: September 2026
Every UPS lists two numbers — VA and watts — and it trips folks up. This guide shows which one is the honest limit, and how to size your gear without math. Rather just ask? My number is (330) 200-8042.
The Two Numbers, at a Glance
A UPS is rated with two numbers. VA (volt-amps) is the bigger, headline number on the front. Watts is the real power it can deliver — the honest limit for your gear, and usually the smaller figure. Add up the watts of what you want to protect, keep it comfortably under the UPS's watts, and leave headroom. These numbers are about how much, not how long. There's a printable 29-page version up top.
Common Questions
1 Which number do I go by — VA or watts?
Watts. It's the honest limit for the electronics you'll plug in. Keep your gear's total watts comfortably under the UPS's watts and you're safe; the VA will almost always be fine too.
2 Why is the VA number bigger?
Because it counts a bit of power that sloshes back and forth without doing work. Watts counts only the real work, so it lands lower — and it's the number that matters for your gear.
3 Do I have to do any math?
No. The maker prints both numbers, and your gear's labels list what they need. You just add up the watts — or send me the labels and I'll add them for you.
4 Does a bigger number mean it runs longer?
No — a common mix-up. VA and watts are about how much it can power at once, not for how long. Runtime is a separate question our sizing guide covers.
5 How much headroom should I leave?
Enough that the UPS isn't running near its limit — a comfortable cushion. That gives you longer runtime, a cooler unit, and room to add gear later.
6 What if the label only shows volts and amps?
Multiply those two for a VA-style figure, or just send me a photo and I'll translate it. Many chargers and power bricks print the numbers right on them.
Would You Rather I Just Help?
Squinting at a UPS box trying to decode VA and watts? Read me the numbers or send photos of your gear's labels, and I'll tell you the size to buy — no math, no sales pitch. $99 flat for an in-home visit, 30-day come-back-free.
Would you rather I just do this for you?
No shame in it — plenty of folks would rather hand it off, and that's what I'm here for. I'll come to your home, set it up right, and make sure it's working before I leave. Flat $99 per visit — no jargon, no upsell, and every visit is 30-day come-back-free.
Not a hardware job? I can often fix it remotely for $49 — a secure screen-share, up to 2 hours, that you watch the whole time and can end whenever (included free for $39/mo Support Plan members, and it counts toward the $99 if it turns out I need to come out).