FNIRSI GC-01
A cheap pocket Geiger counter for a curious first look at background radiation. Serious users will want more sensitivity and logging.
Amazon $51.29$51.29
The FNIRSI GC-01 is the better geiger counter overall, rated 2.9 to 2.8. The GQ GMC-300S wins on features and sensitivity. The FNIRSI GC-01 costs $4.69 less ($51.29 vs $55.98).
Prices were last checked November 9, 2026. Product prices and availability are accurate as of that date and are subject to change; the price and availability shown on Amazon or the retailer's site at the time of purchase apply. As an Amazon Associate we earn from qualifying purchases.
GQ GMC-300S
A basic, cheap beta-gamma counter for checking background levels and hobby samples. Buy it to learn, not for emergencies.
Amazon $55.98$55.98
Which should you buy?
- Choose the GQ GMC-300S for features (data logging vs none of the listed features) and sensitivity (132 CPM per µSv/h (Co-60) vs 80 CPM per µSv/h (Co-60)).
Scores side by side
Each factor is scored 0-100 against the same fixed reference points for every beta-gamma geiger counters geiger counter; a clear win is highlighted. How we rank explains each one.
| Factor weight | FNIRSI GC-01 | GQ GMC-300S |
|---|---|---|
| Overall rating | 2.9/5 | 2.8/5 |
| Sensitivity 25% | 10 80 CPM per µSv/h (Co-60) | 21 132 CPM per µSv/h (Co-60) |
| Radiation types 20% | 40 gamma, X-ray, beta | 40 gamma, X-ray, beta |
| Dose-rate range 15% | 50 dose-rate range not published (neutral score used) | 17 reads up to 328 µSv/h |
| Features 15% | 0 none of the listed features | 35 data logging |
| Price 15% | 100 $51.29 | 100 $55.98 |
| Warranty 10% | 67 2-year warranty | 0 warranty not published, scored as none |
Specifications
| FNIRSI GC-01 | GQ GMC-300S | |
|---|---|---|
| Detection | ||
| Detector | GM tube | GM tube |
| Tube or crystal | energy-compensated GM tube | - |
| Radiation types | β γ X | β γ X |
| Sensitivity | 80 CPM per µSv/h (Co-60) | 132 CPM per µSv/h (Co-60) |
| Max dose rate | - | 328 µSv/h |
| Energy range | 48 to 1,500 keV | 100 to 3,000 keV |
| Gamma spectrum | No | No |
| Features | ||
| Data logging | - | Yes |
| Connection | - | None |
| Battery | 1100 mAh rechargeable lithium | 3.7 V rechargeable Li-ion |
| Build | ||
| Warranty | 2 years | - |