Jeremiah Kowalski with hydrogen water bottles he has tested

Author profile

Jeremiah Kowalski

Founder & Product Tester at Water Bottle Advisor

Jeremiah researches and personally tests reusable water bottles, tumblers, mugs, filtration systems and other hydration products. Since 2023, his work has combined long-term ownership with repeatable measurements for insulation, leak resistance, cleaning, portability, durability and drinking experience. He also researches materials and manufacturer safety documentation when evaluating products.

120+ products personally tested 30+ drinkware brands covered hands-on testing since 2023

Experience

What I test and evaluate

My focus is intentionally narrow: everyday drinkware and hydration products, evaluated on the details that determine whether they are genuinely good to live with.

  • Reusable water bottles
  • Insulated drinkware
  • Lids and drinking systems
  • Thermal performance
  • Cleaning and maintenance
  • Portability and ergonomics
  • Materials and safety claims
  • Hydrogen water bottles

My baseline rule: if I have not personally owned and used a product, I do not publish a hands-on review of it. Product pages and manufacturer claims can inform research, but they do not replace first-hand testing.

  • 24-hour cold and 12-hour hot retention
  • Leak and lid-usability testing
  • Timed disassembly and cleaning
  • Weight, dimensions and cup-holder fit
  • Flow rate and drinking comfort
  • Durability and repeated everyday use

Proof of experience

Hands-on testing in practice

Water Bottle Advisor testing setup with hydrogen bottles, scale and measurement equipment
Original testing setup and measurement equipment.
Water bottle temperature being measured during an insulation test
Controlled cold- and hot-retention measurements.
Jeremiah Kowalski using a reusable water bottle outdoors during real-world use
Real-world use alongside controlled bench testing.

Exact procedures, equipment, thresholds and category-specific protocols are documented separately. See the full testing methodology