Monitor power use rarely shows up in buying decisions, but it can be worth a few minutes of thought, especially if you run multiple screens, work from home full-time, or are choosing between a large bright display and a more modest one. The good news is that the math is simple and the biggest savings come from settings you can change today.
This guide explains what drives a monitor's power draw, how to find the real numbers for any model, and how to calculate your own running cost.
Quick answer
- Brightness is the biggest factor you control. Lowering it to suit your room usually cuts power noticeably on LCDs.
- Bigger, brighter and higher-refresh screens generally draw more. HDR peaks and Mini-LED backlights can raise consumption further.
- OLED power varies with content: dark images use less, bright full-white pages use more.
- To estimate cost: watts × hours per day × days ÷ 1,000 = kWh, then multiply by your electricity rate.
- Standby draw is usually small, but USB-C charging and USB hubs can change that.
What drives a monitor's power use
| Factor | Effect on power | Why |
|---|---|---|
| Brightness setting | Large | On LCDs, the backlight is the main consumer; dimmer means less power |
| Screen size | Large | More area to light |
| Backlight / panel type | Varies | Mini-LED, edge-lit LCD and OLED behave differently |
| HDR mode | Can be large | HDR highlights push brightness much higher than SDR |
| Refresh rate & resolution | Moderate | More processing and pixel switching |
| Built-in USB-C power delivery | Can be large | Power sent to a laptop is drawn from the wall by the monitor |
| Speakers, USB hubs, RGB lighting | Small to moderate | Extra components draw extra power |
The key point: two monitors with the same size can use very different amounts of power depending on brightness and panel technology, and the same monitor can vary widely depending on how you set it up.
LCD vs OLED vs Mini-LED
Standard LCD (IPS, VA, TN)
The backlight stays on behind the whole panel, so power is driven mainly by the brightness setting, not by what's on screen. Turning brightness down saves power whether you're looking at a white document or a dark game.
Mini-LED
Mini-LED uses many small backlight zones that dim independently. Dark content can reduce draw, but bright HDR scenes push zones hard, so peak consumption can be high. In SDR at moderate brightness, behavior is closer to a regular LCD.
OLED
Each pixel makes its own light, so power depends on content. A dark theme, dark game or movie uses less; a full white web page or spreadsheet uses more. Dark mode in your apps genuinely reduces OLED power, and as a bonus it also reduces the static bright elements that matter for burn-in risk. See our OLED longevity guide.
How to find a monitor's real power numbers
The "maximum power" figure on a spec sheet is often a worst case: maximum brightness, speakers loud, USB ports loaded and sometimes USB-C charging at full output. It isn't what you'll typically use.
- Look for "typical" or "on mode" power in the detailed specs or datasheet. This is closer to everyday use.
- Check energy labels. Depending on your region, monitors may carry an energy label (such as the EU energy label) or an ENERGY STAR certification, both of which give standardized comparisons.
- Separate out USB-C power delivery. A monitor rated with a large total power may be including the wattage it can send to a laptop.
- Measure it yourself. A plug-in power meter shows actual watts at the wall, under your own settings. It's the only way to know your real number.
How to calculate your running cost
Electricity is billed in kilowatt-hours (kWh). Here's the formula:
watts × hours per day × days per year ÷ 1,000 = kWh per yearkWh per year × your price per kWh = yearly cost
Worked example (illustrative numbers)
Say a power meter shows your monitor drawing 30 watts at your normal brightness, you use it 8 hours a day, 250 days a year, and your electricity costs $0.20 per kWh. (Use your own numbers; these are just to show the math.)
- 30 W × 8 h = 240 Wh per day
- 240 Wh × 250 days = 60,000 Wh = 60 kWh per year
- 60 kWh × $0.20 = $12 per year
Now double the wattage and the hours, for example a large, bright screen used most of the day, every day, and the cost scales accordingly. The formula makes it easy to compare two monitors you're considering, or to see how much a brightness change saves.
| Your inputs | Where to find them |
|---|---|
| Watts | Plug-in power meter, or "typical" power in the spec sheet |
| Hours per day | Your own habits; include gaming and evening use |
| Days per year | Workdays only, or every day |
| Price per kWh | Your electricity bill |
How to cut power use without hurting comfort
- Lower brightness to match your room. It's also usually more comfortable. Our monitor setup guide shows how.
- Set a sensible sleep timer in your OS so the display turns off when you step away.
- Turn off unused extras: RGB lighting, built-in speakers you don't use, always-on USB charging.
- Use dark mode on OLED to reduce content-dependent power.
- Add a smart plug with energy monitoring if you want to track usage over weeks; some apps can also schedule power-off. Browse energy-monitoring smart plugs.
- Use HDR only when you want it. Leaving HDR on for desktop work can raise brightness and power without benefit.
- Consider fewer or smaller screens if a second monitor sits mostly idle.
- Use a switched power strip if you want to eliminate standby draw overnight, as long as the monitor and its firmware are fine with full power-off.
Standby and "off" power
When a monitor goes to sleep or is switched off with its button, it usually still draws a small amount of power to watch for a signal or button press. For a single monitor this is typically minor next to on-mode power.
Some features increase standby draw: keeping USB ports powered for charging, USB-C power delivery staying active, or "quick wake" options. If standby matters to you, look in the monitor's menu for settings like USB charging in standby or deep sleep, and turn off the ones you don't need.
A note on USB-C monitors and laptops
If your monitor charges your laptop over USB-C, it's acting as the laptop's power supply too. The monitor's wall draw will rise by roughly what the laptop is pulling, minus the laptop charger you're no longer using. Total household consumption doesn't necessarily go up, it just shifts from the laptop's charger to the monitor. Keep that in mind when you see a USB-C monitor's higher maximum power rating. Our USB-C power delivery guide explains the wattage tiers.
Should power use change which monitor you buy?
For most people, a monitor's running cost is modest compared with its purchase price, so it shouldn't outweigh picture quality, size or ergonomics. Where it can make a difference:
- Multi-monitor desks running long hours every day.
- Very large or very bright displays, including TVs used as monitors.
- Regions with high electricity prices.
- Off-grid, battery or solar setups where every watt counts.
In those cases, compare "typical" power figures or energy labels between your shortlisted models, and plan to run at moderate brightness.
FAQ
How many watts does a monitor use?
It varies widely by size, panel type and brightness. Check the "typical" power in the spec sheet or energy label, or measure it at the wall with a plug-in power meter for an exact figure under your settings.
Does a higher refresh rate use more power?
Generally a little more, due to extra processing and faster pixel switching, but brightness and screen size usually have a much bigger effect.
Do OLED monitors use less power than LCD?
It depends on content. OLEDs use less with dark content and more with bright, full-white content. For bright office work, an OLED may not save power.
Is it worth turning my monitor off at night?
Sleep mode already reduces power a lot, but fully switching off or using a switched power strip removes the small standby draw. It's a minor saving per monitor that adds up across multiple screens.
Does a USB-C monitor increase my power bill?
It increases the monitor's own draw when it charges a laptop, but that power would otherwise go through the laptop's charger. The overall change is usually small.
The bottom line
Monitor power use is easy to understand once you know the drivers: brightness, size, panel type and HDR. Measure or look up the typical wattage, run the simple formula with your electricity rate, and you'll know exactly what your screen costs. Then lower brightness to a comfortable level and set a sleep timer. Those two changes alone deliver most of the savings.