Terms of Use

By using WaterHeaterCalcs.com you agree to these terms.

1. Service

WaterHeaterCalcs provides free, informational water-heater sizing, energy and cost calculators and reference content. Use requires no account.

2. Estimates only — not professional advice

All results are deterministic estimates computed from the inputs and prices you provide and standard reference conventions. They are for planning and education and are not a bid, a contract, an installation procedure, a gas / combustion / venting, temperature-&-pressure relief, scald / Legionella-medical or code-compliance determination, a code-compliance certificate, or safety advice. Get itemized written quotes from licensed, insured plumbers, confirm your unit’s rated First-Hour Rating, GPM and UEF on its EnergyGuide label, and follow the manufacturer’s instructions and local code.

3. No warranty

The site is provided "as is" without warranties of any kind. While the formulas are tested against known values, we do not guarantee that any result fits your specific situation. You are responsible for verifying figures and measurements before relying on them.

4. Limitation of liability

To the extent permitted by law, Redbit S.r.l.s. is not liable for any damage arising from use of the site or reliance on its results.

5. Intellectual property

Content and design are protected. You may use the calculators for personal and professional purposes; you may not copy the site's content wholesale.

6. Provider

Redbit S.r.l.s., Viale della Grande Muraglia 494, 00144 Rome, Italy (VAT IT15237911001). Contact: [email protected].