HOBO U26-001 Dissolved Oxygen Data Logger


HOBO Data Loggers by Onset

Not in stock. Usually ships in 1-2 weeks [?]

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  • Measurement range: 0 to 30 mg/L
  • Accuracy: 0.2 mg/L
  • Optical DO sensor technology
  • Resolution: 0.02 mg/L
  • 21,700 sets of DO and temperature measurements
  • 1 minute to 18 hours logging rates
  • Wide variety of applications

The HOBO U26-001 Dissolved Oxygen Data Logger measures concentrations of dissolved oxygen in lakes, streams, rivers, estuaries, and coastal waters. Used by aquatic biologists, hydrologists, and other research professionals to monitor water quality, the U26 is ideal for climate change and environmental impact studies as well as ecological and oceanographic research.

The HOBO U26 combines the high-accuracy, robust performance of industry-leading RDO® Basic (Rugged Dissolved Oxygen) sensor technology with an easy-to-maintain design, all at a fraction of the cost of other monitoring options.

Required Components

These additional components are required for the operation of your product. We strongly advise you to purchase these components unless you already own them or own a suitable alternative.

HOBO U-DTW-1 Waterproof Shuttle Data Transporter
Compatible with all HOBO U-Series loggers with optic USB, waterproof up to 20m (66ft), requires HOBOware Pro software
HOBO BASE-U-4 Optic USB Base Station
Used to offload data from any HOBO data logger with an Optic USB interface, splash resistant
In Stock
HOBO U26-RDOB-1 DO Sensor Cap
Replacement dissolved oxygen sensor cap that has a 2-year shelf life and 6-month deployment life


HOBO HOBOware Pro Software
Plot or export data to spreadsheets, time saving tools to fast setup, readout and export, compatible with all HOBO data loggers
In Stock


Please consider these optional accessories.

HOBO U26-GUARD-2 Antifouling Protective Guard
Replaces standard protective guard & uses copper windings to reduce bio-fouling while still allowing good water flow to the sensor


This product can be used in the following applications: