# Bluelab pH Pen vs VIVOSUN Digital pH Meter Pen Tester for Water & Hydroponics: specs and price compared

A sourced, side-by-side comparison of the Bluelab pH Pen (Bluelab) and VIVOSUN Digital pH Meter Pen Tester for Water & Hydroponics (VIVOSUN) among ph meters. VIVOSUN Digital pH Meter Pen Tester for Water & Hydroponics is the cheaper of the two at $8.55.

## Side by side

| Spec | Bluelab pH Pen | VIVOSUN Digital pH Meter Pen Tester for Water & Hydroponics |
| --- | --- | --- |
| US price | $99 | $8.55 |
| Brand | Bluelab | VIVOSUN |
| Ph range | 0.0 to 14.0 | 0.00 to 14.00 |
| Resolution ph | 0.1 | 0.01 pH |
| Accuracy ph | ±0.1 at 25°C/77°F | ±0.01 pH |
| Calibration points | Two-point (pH 7.0 and pH 4.0 solutions), with a built-in 30-day calibration reminder | 3-point (calibration buffer powders included) |
| Atc | Yes, fully temperature compensated | Yes |
| Electrode type | Double-junction pH probe | — |
| Waterproof rating | Waterproof; floats in any solution | — |
| Battery type | 1 x AAA alkaline | 2 x 1.5V button cell (built-in) |

## Key differences

- Ph range: Bluelab pH Pen 0.0 to 14.0 vs VIVOSUN Digital pH Meter Pen Tester for Water & Hydroponics 0.00 to 14.00
- Resolution ph: Bluelab pH Pen 0.1 vs VIVOSUN Digital pH Meter Pen Tester for Water & Hydroponics 0.01 pH
- Accuracy ph: Bluelab pH Pen ±0.1 at 25°C/77°F vs VIVOSUN Digital pH Meter Pen Tester for Water & Hydroponics ±0.01 pH
- Calibration points: Bluelab pH Pen Two-point (pH 7.0 and pH 4.0 solutions), with a built-in 30-day calibration reminder vs VIVOSUN Digital pH Meter Pen Tester for Water & Hydroponics 3-point (calibration buffer powders included)
- Atc: Bluelab pH Pen Yes, fully temperature compensated vs VIVOSUN Digital pH Meter Pen Tester for Water & Hydroponics Yes
- Battery type: Bluelab pH Pen 1 x AAA alkaline vs VIVOSUN Digital pH Meter Pen Tester for Water & Hydroponics 2 x 1.5V button cell (built-in)

## Sources

- Bluelab pH Pen: https://www.bluelab.com/products/bluelab-ph-pen (bluelab.com, verified 2026-08-12)
- VIVOSUN Digital pH Meter Pen Tester for Water & Hydroponics: https://www.amazon.com/VIVOSUN-Meter-Digital-Tester-Water/dp/B01M5IASHD/ (amazon.com, verified 2026-08-12)

Canonical: https://frontdeskreview.com/gear/ph-meters/bluelab-ph-pen-vs-vivosun-ph-meter/
Cite: Per The Front Desk Review, Bluelab pH Pen ($99) vs VIVOSUN Digital pH Meter Pen Tester for Water & Hydroponics ($8.55) — sourced spec-by-spec comparison at https://frontdeskreview.com/gear/ph-meters/bluelab-ph-pen-vs-vivosun-ph-meter/
License: CC BY 4.0.