Tools & DIY · Head-to-head
Thermal Master P3 vs Seek Thermal Nano 300
Which should you buy? Our verdict on both, pulled from our full The Best Thermal Imaging Cameras: 4 Compared (and One to Skip) comparison.
The Thermal Master P3 delivers the best mix of image quality, speed and versatility for the money, and its built-in macro lens is a genuine trump card. The Seek Thermal Nano 300 is the pick when you want the sharpest, widest view for scanning rooms and buildings.

Thermal Master P3
Buy itA pocket 256 x 192 phone camera with a built-in 8 mm macro and manual focus lens for close-up electronics work.
- Native 256 x 192 VOx sensor with a stated NETD under 35 mK and a 25 Hz refresh
- Built-in 8 mm manual-focus macro lens, so close-up PCB work needs no clip-on accessory
- Small 59 x 27 x 17.2 mm alloy body that runs on a stated 0.32 W from the phone
- Listed -20 to 600 degrees C range at plus or minus 2 degrees C or 2 percent
- No screen of its own, so it needs a compatible phone or PC
- USB-C plug; Lightning iPhones go through the included adapter, and Thermal Master does not publish a weight

Seek Thermal Nano 300
Buy itThe highest native resolution of the group, with a wide field of view for scanning whole rooms and buildings.
- True 320x240 sensor, the sharpest native resolution here
- Wide 57 x 42 degree field of view takes in a large part of a wall or ceiling at once
- Fast 25Hz refresh and 35 mK thermal sensitivity for spotting subtle differences
- USB-C and Lightning versions cover modern iPhones and Android phones
- Seek's page lists measurement accuracy of 5 degrees C or 5 percent, looser than the 2 degrees C or 2 percent Thermal Master and Topdon list
- No macro lens and no built-in screen
Side by side
| Thermal Master P3 | Seek Thermal Nano 300 | |
|---|---|---|
| Our verdict | Buy | Buy |
| Best for | Hobbyists, makers and electronics/PCB troubleshooters who want the best image-per-dollar in a pocket-sized package. | Home inspectors, HVAC techs and anyone chasing insulation gaps, drafts or moisture across large surfaces. |
| Price tier | $ · mid-range | $ · mid-range |
The bottom line
Our overall pick is the Thermal Master P3 - A pocket 256 x 192 phone camera with a built-in 8 mm macro and manual focus lens for close-up electronics work. Choose the Seek Thermal Nano 300 instead if home inspectors, HVAC techs and anyone chasing insulation gaps, drafts or moisture across large surfaces.
Want the full picture, including the other options we compared and the popular one we'd skip? Read the complete The Best Thermal Imaging Cameras: 4 Compared (and One to Skip).