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Free Tool

Water Heater Flush Schedule Calculator

Answer a few questions and this calculator tells you roughly when to next drain or flush your water heater, then lets you download a one-click calendar reminder so you actually remember. Everything runs in your browser: no email, no sign-up, nothing leaves your device.

What kind of water heater do you have?

Not sure? Check your local utility's water quality report or use a hardware-store test strip. Leave blank to use the standard once-a-year baseline.

Leave blank if you have never flushed it or cannot remember. We will schedule from today instead.

How this calculator decides

This tool does not invent new advice. It reuses the exact flushing schedule already published in our guide How Often Should You Flush a Water Heater? and the hardness bands from Hard Water Effects on Water Heaters. When more than one rule applies, it uses the shortest (most protective) interval, which is exactly what those guides recommend when factors stack up.

Situation Recommended frequency
Hard water (above 7 GPG), no softenerEvery 6 months
Moderate water (3-7 GPG), no softenerEvery 12 months
Soft water or whole-house softenerEvery 12-18 months
Heavy usage (5+ people)Every 6-9 months
Tank older than 8 yearsEvery 6 months
Tankless water heaterDescale every 12-18 months

These figures are general maintenance guidance, not a guarantee about your specific tank. Always follow your manufacturer's manual, and if you hear popping or rumbling or see other signs it needs flushing, flush it sooner regardless of the date this tool gives you.

Ready to do the job?

When your reminder comes due, follow our step-by-step flushing guide or draining guide. Tankless owners can use our descaling kit picks.