9 Best Carbon Monoxide Detectors That Show Levels (November 2026)
The best carbon monoxide detectors with digital displays include the Kidde Carbon Monoxide Detector for plug-in home monitoring, the Kidde Carbon Monoxide Detector for CO and explosive gas, and the X-Sense Smoke Detector and Carbon Monoxide Detector for smoke and CO in one unit.
On this page (7 sections)
- How we chose carbon monoxide detectors with displays
- Compare the best CO detectors that show levels
- Best carbon monoxide detectors with digital displays
- What should you compare in a CO detector that shows levels?
- Are displayed CO numbers safe to interpret on their own?
- Where should a detector with a display go?
- Which carbon monoxide detector with levels should you choose?
The best carbon monoxide detector that shows levels for most homes is the Kidde plug-in model with a digital LED display. It shows the CO level it senses, has a 9V battery backup, and stores a peak level in memory.
A display can make a detector's readings easier to understand, but the screen is not a replacement for its alarm. For a household alarm, prioritize a model designed for residential use, then compare power, display behavior, backup options and where you can install it.
Our picks at a glance
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1
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2
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3
Best for smoke and CO in one unitX-Sense Smoke Detector and Carbon Monoxide Detector
9.5/10 our score
See it on Amazon
- 4
Check itTOPTES CT-580 Portable Carbon Monoxide Detector
Best for portable spot checks - 5
Check itSiterlink Carbon Monoxide Detectors Plug
Best for compact outlet placement - 6
Check itSITERWELL Plug in Carbon Monoxide Detector
Best for a plug-in alarm with backup - 7
Check itHeiman Carbon Monoxide Detectors
Best for low-level readings on screen - 8
Check itTOPTES CT-913 Portable Carbon Monoxide Detector
Best for portable readings with trends - 9
Check itSITERWELL Carbon Monoxide Detector 7 Year Product
Best for a battery-powered LCD alarm
How we chose carbon monoxide detectors with displays
The best carbon monoxide detector with levels should make its readings useful without confusing a portable inspection tool with a household alarm. We compared the stated display, power source, alarm features and intended use for each pick.
A numeric display matters most when you want to see readings or review a stored peak. Some picks have a numeric screen, while others are included as outlet alarms whose available details don't confirm one, so check that distinction before choosing.
The products here aren't all interchangeable. TOPTES describes its CT-580 and CT-913 as portable tools, while the Kidde, X-Sense, Heiman and SITERWELL models are alarms intended for home or residential placement.
Compare the best CO detectors that show levels
The Kidde plug-in models combine a digital display with audible alerts, while Heiman gives a low-level LCD reading and TOPTES offers portable trend tracking. Check the power and use type in the table before comparing extra features.
| Product | Best for | Power | Display | Alarm | Our score |
|---|---|---|---|---|---|
| Kidde Carbon Monoxide Detector | plug-in home monitoring | 120V plug-in with 9V battery backup | Digital LED shows sensed CO level | 85 dB audible alarm | 9.7 |
| Kidde Carbon Monoxide Detector | CO and explosive gas | 120V plug-in with 9V battery backup | CO level or GAS indicator | 85 dB audible alarm | 9.7 |
| X-Sense Smoke Detector and Carbon Monoxide Detector | smoke and CO in one unit | 10-year sealed battery | LCD for real-time CO and battery status | 85 dB audible alarm | 9.5 |
| TOPTES CT-580 Portable Carbon Monoxide Detector | portable spot checks | TFT color display | 9.3 | ||
| Siterlink Carbon Monoxide Detectors Plug | compact outlet placement | AC with stated 10-year battery backup | No numeric display detail provided | 9.2 | |
| SITERWELL Plug in Carbon Monoxide Detector | a plug-in alarm with backup | Corded electric with stated 10-year battery | Numeric display is not confirmed | Audible warning over 85 dB | 8.8 |
| Heiman Carbon Monoxide Detectors | low-level readings on screen | 2 replaceable AA batteries | LCD shows live readings from 20–999 ppm | 8.6 | |
| TOPTES CT-913 Portable Carbon Monoxide Detector | portable readings with trends | Rechargeable 4000 mAh battery | TFT color screen with trend graph | 8.3 | |
| SITERWELL Carbon Monoxide Detector 7 Year Product | a battery-powered LCD alarm | 2 AA batteries | LCD shows real-time CO levels | 8.1 |
Best carbon monoxide detectors with digital displays
The right model depends on whether you need an installed home alarm, a combined smoke and CO unit, or a portable meter for checks. Start with the products whose displays and intended use match your need.
Kidde Carbon Monoxide Detector: Best for plug-in home monitoring
- Digital LED display shows sensed CO level
- 9V battery backup
- 85 dB alarm
- Peak Level Memory
A digital readout, battery backup and Peak Level Memory make this a practical fit for a home outlet. Its display shows the level the alarm is sensing.
Pros
- Shows sensed CO level
- Battery backup during a power outage
- Peak Level Memory
Cons
- Needs a nearby outlet
- Display type is LED rather than a larger color screen
The Kidde plug-in detector is the best fit for most buyers who want to see the CO level an alarm is sensing. The digital LED display, 9V battery backup and Peak Level Memory cover the main reasons people choose a detector with numbers.
It plugs into a standard 120V outlet, and the battery backup is intended to keep it operating during a power outage. Peak Level Memory records the last time CO was detected or when the unit was tested, giving you another reading to review.
This is a residential alarm with an 85 dB audible alert. The display updates the sensed CO level, but read the manual to understand the alarm pattern and what to do if the unit alerts.
Choose it when you want an outlet-powered home alarm with a displayed level and a stored peak. For a closer look at this brand's display models, see our guide to best Kidde carbon monoxide detectors with displays.
Kidde Carbon Monoxide Detector: Best for CO and explosive gas
- Digital LED display shows CO level
- Displays GAS for explosive gas
- 9V battery backup
- Peak Level Memory
This plug-in Kidde combines a CO level display with an alert for explosive gas. The digital display shows the CO level it senses or the word GAS when explosive gas is present.
Pros
- Displays CO level and GAS indicator
- Battery backup
- Peak Level Memory
Cons
- Needs a nearby outlet
- The display uses an indicator for gas rather than a numeric gas reading
This Kidde is the pick for households that also want an explosive gas alarm. Its display shows the CO level it senses and displays GAS when explosive gas is detected.
It plugs into a standard 120V outlet and has a 9V battery backup. Peak Level Memory records the last time CO was detected or the unit was tested, and the alarm sounds at 85 dB when CO or explosive gas is detected.
The gas alert is a separate function from a numeric CO reading. The screen uses the word GAS for explosive gas rather than giving a concentration for that gas.
Choose this model if you want a plug-in CO detector that also alerts for explosive gas. If you want to compare other plug-in readouts, our guide to digital plug-in carbon monoxide detectors covers that format.
X-Sense Smoke Detector and Carbon Monoxide Detector: Best for smoke and CO in one unit
- Smoke and CO detection
- Real-time CO and battery LCD display
- 10-year sealed battery
- 85 dB alarm
The SC01 combines smoke and CO alarms in a standalone unit with an LCD for real-time CO and battery information. It runs on a sealed battery and does not support wireless interconnection.
Pros
- Smoke and CO protection in one unit
- Real-time CO and battery LCD
- No rewiring required
Cons
- Does not support wireless interconnection
- Battery is sealed rather than replaceable
The X-Sense SC01 fits a home that needs smoke and CO detection in one standalone unit. Its LCD displays real-time CO and battery information, and a sealed battery powers the alarm for its 10-year life.
Installation doesn't require rewiring, and the unit mounts to a wall or ceiling. It has an 85 dB alarm and is described as meeting UL 217 and UL 2034 standards.
The SC01 does not support wireless interconnection, Wi-Fi or a base station. Choose it if a combined alarm and display suit your setup, and confirm the placement and number of alarms you need for your home.
For a wider look at combined units, see our guide to best combination smoke and CO detectors.
TOPTES CT-580 Portable Carbon Monoxide Detector: Best for portable spot checks
- Portable TFT color display
- 0–1000 ppm detection range
- Audible, visual and vibration alarms
- USB-C charging
The rechargeable CT-580 is a portable tool for checking changing CO readings. It has a graphical display, three alarm modes and a stated 0–1000 ppm detection range.
Pros
- Portable color display
- Audible, visual and vibration alarms
- USB-C charging
Cons
- Manual inspection tool, not a fixed household alarm
- Requires charging
The TOPTES CT-580 is best for portable spot checks where a screen and changing readings matter. It has a TFT color display, a stated detection range of 0–1000 ppm and audible, visual and vibration alarms.
TOPTES describes it as a manual inspection tool for personal or business use. It is rechargeable by USB-C and includes a built-in flashlight, adjustable screen brightness and auto screen-off.
That use is different from leaving a residential alarm installed to warn people in the home. Use a proper household CO alarm for that job, and treat this portable device as a separate tool for checks.
Choose the CT-580 if you want a rechargeable portable detector with three alarm modes. Its graphical display and carrying case make it the most inspection-focused pick in this group.
Siterlink Carbon Monoxide Detectors Plug: Best for compact outlet placement
- AC plug-in operation
- 10-year battery backup
- Foldable plug
- Electrochemical sensor
A foldable plug and travel-size design suit buyers who want an outlet-powered alarm that packs more easily. The available feature details do not describe a numeric CO display, so confirm that feature if readings are essential.
Pros
- Foldable plug
- Stated battery backup
- Electrochemical sensor
Cons
- Numeric display is not confirmed
- Outlet required for AC operation
The Siterlink plug-in alarm suits buyers who want a compact outlet device with backup power and a foldable plug. It has an electrochemical sensor and a stated 10-year battery backup.
The available features describe a soft green status light, but they don't confirm a numeric CO display. Since this roundup focuses on carbon monoxide detectors that show levels, treat this as a secondary option and verify the display before buying if numeric readings are a must.
Its foldable plug is a useful detail for carrying the alarm during travel. The stated AC operation still means you'll need an outlet when using it in that mode.
Choose it when compact outlet placement and backup are priorities, and confirm the display behavior first. It doesn't outrank the models with a clearly described numeric screen for reading CO levels.
SITERWELL Plug in Carbon Monoxide Detector: Best for a plug-in alarm with backup
- AC powered
- 10-year battery backup
- Electrochemical sensor
- Audible warning over 85 dB
SITERWELL describes this as an AC-powered alarm with a 10-year battery and an electrochemical sensor. Its details don't confirm a numeric display, so consider it only if an alarm and backup power matter more than seeing readings.
Pros
- AC power with stated battery backup
- Electrochemical sensor
- Portable form
Cons
- Numeric CO display is not confirmed
- No displayed reading details
The SITERWELL plug-in alarm is aimed at buyers who want AC operation, battery backup and an audible warning. Its electrochemical sensor and breathing-style status light are the main described features.
The product details say it has a 10-year battery and an audible warning above 85 dB. They don't confirm that it shows a numeric CO level, so it is a weaker fit if seeing numbers is your main reason for choosing a detector.
The color indicators are described as green for normal operation, yellow for fault and red for alarm. Those lights communicate status, but they are not a substitute for a digital reading.
Choose this if backup power and a plug-in format matter more than a numeric display. If the screen is essential, favor a model above with a confirmed live or sensed CO readout.
Heiman Carbon Monoxide Detectors: Best for low-level readings on screen
- Real-time LCD readings from 20 ppm
- 30 ppm early warning
- 12-hour alarm memory
- 2 AA batteries
Heiman pairs a live LCD reading that starts at 20 ppm with a staged alert system. It runs on two replaceable AA batteries and is designed for residential use.
Pros
- Live readings from 20 ppm
- Early warning at 30 ppm
- 12-hour alarm memory
Cons
- Battery powered, not plug-in
- Specified operating range is 40°F to 100°F
Heiman is the standout choice for buyers who want a display that starts showing low-level readings. Its LCD displays live readings from 20 to 999 ppm, and its described alert system includes an early warning at 30 ppm and a separate 85 dB danger alarm.
The detector runs on two replaceable AA batteries and can sit on a table or mount on a wall. It also stores alarm memory for 12 hours, which can help you see whether an event happened while you were away.
Heiman specifies an operating temperature range of 40°F to 100°F and says performance may be compromised outside it. It is intended for residential alarm use, not garages, workshops or locations directly under vehicle exhaust.
Choose Heiman if low-level readings on an LCD are your priority. Our guide to carbon monoxide detectors for low levels explores that use in more detail.
TOPTES CT-913 Portable Carbon Monoxide Detector: Best for portable readings with trends
- Real-time TFT readings
- Trend graph
- 0–1000 ppm range
- Visual, audible and vibration alarms
The CT-913 shows real-time PPM values and a trend graph, making it useful for observing changing readings during checks. It is rechargeable and offers visual, audible and vibration alarms.
Pros
- Trend graph and real-time readings
- Three alarm modes
- USB-C charging
Cons
- Portable tool rather than a fixed household alarm
- Needs charging
The TOPTES CT-913 is best for portable checks where you want to watch how readings change over time. Its TFT color display shows real-time PPM values and a trend graph, with a stated detection range of 0–1000 ppm.
The rechargeable 4000 mAh battery is described as providing over 60 hours of operation. The detector also has visual, audible and vibration alarms, plus alarm record storage and zero calibration functions.
Like the CT-580, this is a portable inspection tool rather than a fixed home alarm. Its trend graph can help with observing changes during inspections, but it should not replace residential alarms.
Choose the CT-913 if you want a portable display that includes a graph. The CT-580 is a simpler portable option if the trend view and longer stated battery runtime are not your priorities.
SITERWELL Carbon Monoxide Detector 7 Year Product: Best for a battery-powered LCD alarm
- LCD shows real-time CO levels
- 2 AA batteries
- Red, green and yellow status lights
- Wall-mount or freestanding
This SITERWELL alarm combines a real-time LCD with colored status lights and flexible placement. Its stated product life is 7 years.
Pros
- Real-time LCD readings
- Wall-mounted or freestanding
- Colored status indicators
Cons
- Battery powered
- Does not specify the display's measurement range
The SITERWELL GS828A suits buyers who want a battery-powered home alarm with a real-time LCD. The screen shows CO levels, and red, green and yellow lights indicate alarm, power or fault status.
It runs on two AA batteries and can be mounted on a wall or used freestanding. The stated product life is 7 years, and the detector has an audible alarm.
The feature details do not specify the display's measurement range. If you need to know exactly which low readings appear, compare that point with a detector that states its range before deciding.
Choose this model for flexible placement and a clear LCD in a battery-powered format. It may be less suitable if you need a particular ppm display threshold.
What should you compare in a CO detector that shows levels?
A CO detector that shows levels should state what its display measures and whether it is an alarm for home use or a portable inspection tool. Those two details matter more than screen size or color.
Readout type: A live reading shows the level the detector senses, while Peak Level Memory stores a past peak or event. Check the manual to understand how the display and memory work.
Power: Plug-in models need an outlet, and battery backup can keep them running during a power outage. Battery-powered models allow placement away from outlets, while rechargeable portable meters need charging.
Alarm and purpose: A display should sit alongside a clear audible alarm for a residential detector. A portable meter may help with checks, but it isn't the same as an installed home alarm.
For a model-specific explanation, see how to read a carbon monoxide detector. Kidde owners can also use our guide to Kidde carbon monoxide detector readings.
Are displayed CO numbers safe to interpret on their own?
No, a displayed CO number should not be used by itself to decide whether to stay in a building. Use the detector's alarm instructions, and leave immediately if an alarm sounds.
Carbon monoxide is colorless and odorless, so you cannot confirm a safe condition by smell. If anyone has symptoms that could be related to CO exposure, get outside and contact emergency services or a medical professional.
A detector's screen has limits based on its sensor, display behavior and instructions. Use a residential alarm designed for the space, keep it maintained as directed, and don't use a portable reading as a substitute for safety guidance.
Where should a detector with a display go?
Place residential CO alarms according to the device instructions and local guidance, especially near sleeping areas and on each level where required. A display does not change the need for proper alarm placement.
Before installing, check whether the model is intended for a wall, ceiling, outlet or tabletop. Avoid placing a detector outside its stated temperature range or in a location its instructions exclude.
For related household safety, our smoke alarm buying guide explains how to compare standalone smoke alarms with combination devices. A smoke alarm and CO alarm detect different hazards, even when they share one housing.
Which carbon monoxide detector with levels should you choose?
Pick the Kidde plug-in detector for a home alarm with a displayed CO level, battery backup and peak memory. Choose Heiman if you want a stated low-level LCD range, or TOPTES if you need a portable meter for inspection work.
If you want both smoke and CO detection in one standalone unit, consider the X-Sense SC01. For any alarm, follow the manual and your local placement guidance, and leave immediately if it sounds.
Our top 3 picks at a glance
-
1
-
2
-
3
Best for smoke and CO in one unit
X-Sense Smoke Detector and Carbon Monoxide Detector
9.5/10 our score
See it on Amazon
Frequently asked questions
What does a digital carbon monoxide detector display?
A digital CO detector may show a current reading, a peak reading stored in memory, or status information, depending on its design. Check the manual to learn what each number and indicator means.
A displayed number does not replace the alarm or the steps in the detector's safety instructions.
Can a CO detector show levels without sounding an alarm?
Some detectors display readings before reaching an alarm threshold, but the behavior depends on the model. Heiman describes a 30 ppm early warning and a separate danger alarm, while its LCD starts showing live readings at 20 ppm.
Follow the device manual and leave the area if an alarm sounds.
Is a portable CO meter the same as a home alarm?
No. A portable meter such as the TOPTES CT-580 is described as a manual inspection tool, while a household alarm is intended to remain installed and alert occupants.
Use a listed residential alarm for home protection, and don't rely on a portable meter as a substitute.
What should I do if my carbon monoxide alarm sounds?
Leave the building and get everyone outside into fresh air when a CO alarm sounds. Call emergency services or your local fire department from outside, and don't re-enter until responders say it's safe.
Don't use the display alone to decide whether to stay inside.
