Oakton pHTestr 30
#3 in Pen testersFull review
A lab-brand pocket tester with a replaceable module, for labs and schools that already stock Oakton parts.
Amazon $136.22$136.22
±0.01 pH3-pointNone
3.6/5
A pen with a flat electrode for checking cheese, meat, paper or wet surfaces as well as liquids.
- ±0.01 pHAccuracy
- WaterproofWaterproof
- YesReplaceable probe
Check price at Amazon$129.50
Price checked November 8, 2026. As an Amazon Associate we earn from qualifying purchases.
Pros
- Flat-surface electrode reads semi-solids and wet surfaces as well as liquids
- ±0.01 pH accuracy
- Stores 15 readings
Cons
- Extech publishes no warranty or calibration point count
How it scores
The rating comes from 6 measured or published factors, each scored 0-100 against fixed reference points for its type. How we rank explains each one.
Specifications
| Model number | PH100 |
|---|---|
| pH measurement | |
| Accuracy | ±0.01 pH |
| Resolution | 0.01 pH |
| Range | 0 to 14 pH |
| Temperature compensation | Yes |
| Other readings | |
| Conductivity (EC/TDS) | No |
| ORP | No |
| Salinity | No |
| Build | |
| Replaceable probe | Yes |
| Waterproof rating | Waterproof |
| Stored readings | 15 readings |
Alternatives in this type
VIVOSUN AeroLab pH Pen
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A low-cost grower’s pen with a replaceable probe. Its maker publishes little beyond the accuracy claim.
Amazon $65.99$65.99
±0.01 pHNone
Bluelab OnePen
#6 in Pen testersFull review
A connected pen for serious hydroponic growers who want pH and nutrient readings logged to their phone. Most buyers get more for less from the Apera PC60.
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±0.05 pH2-pointEC/TDS
Compare
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