Rank #9 in Best Air Quality Monitor 2026: Fewer Numbers, Better Sensors
Temtop S1 Air Quality Monitor, PM2.5 AQI, Colour LCD
Price and rating as shown on Amazon when we collected them. Both change.
The Temtop S1 is the cheapest monitor in this ranking at £29.99, and it measures PM2.5 particles, an AQI number, temperature and humidity on a colour LCD. Battery life is rated at up to 60 days in ECO mode or around 20 days in smart mode, and it weighs 160g.
It is ninth on purpose: no CO2, no VOCs, and an AQI figure derived from the particle reading rather than measured. What is interesting is its rating shape — 39 per cent of its 130 ratings are four stars rather than five, which says the device works with one annoyance rather than failing.
How those 130 ratings break down
An average hides its own shape. This is the spread behind the 4.2 stars.
Specification
Exactly as published on the Amazon listing, field for field.
| What it measures | PM2.5, AQI, temperature, humidity |
|---|---|
| Display | Colour LCD |
| Battery | Up to 60 days in ECO mode |
| Ratings | 4.2 from 130 |
| Item weight | 160 g |
| Price | £29.99 |
What buyers actually say
Quoted from customer reviews on Amazon
Verified purchase“Twined with a air purifier this is a must for people with breathing difficulties”
Verified purchase“Really nice sensor at a decent price. Has proved reliable with good battery life.”
What it is up against
The rivals it was ranked against in Best Air Quality Monitor 2026: Fewer Numbers, Better Sensors.
Rank #1
Aranet4 Home Wireless Indoor Air Quality Sensor, NDIR CO2 Monitor
£189.00
Rank #2
Temtop M2000 2nd Air Quality Monitor, PM2.5 PM10 CO2 HCHO
£158.64
Rank #3
Temtop Air Quality Monitor LKC1000S+ 2nd, PM2.5 PM10 HCHO TVOC
£129.99
Rank #4
Airthings 2960 View Plus, Radon and Air Quality Monitor with PM2.5
£166.99
Questions people ask
Does it measure CO2?
No. It measures PM2.5 particles, an AQI number, temperature and humidity. For CO2 you need the Aranet4, the SONOFF or the Temtop C1.
What do ECO and Smart modes do?
ECO mode samples less often, with battery life rated at up to 60 days; smart mode samples more often for around 20 days.
Why are so many reviews four-star?
39 per cent of its 130 ratings are four stars rather than five, which usually means the product works with one annoyance. Here the reviews mention battery life and sampling.
Is the AQI number a measurement?
It is derived from the particle reading onto a 0-500 scale. The PM2.5 figure behind it is the measurement.
Who is it for?
Anyone who wants a cheap particle reading, or wants to check whether an air purifier is making a difference in one room.
How many ratings does it have?
130 at the time of collection, averaging 4.2 stars, with 49 per cent five-star and 5 per cent one-star.
Comments
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