5 free calculators and lookups. Each one prefills your ZIP and shows its math.
Answers: what size generator do I need?
Tick what you need to run in an outage. Get running and starting watts, and a generator size adjusted for your elevation and summer heat.
Adjusts for your elevation and summer heat
Answers: how much salt do I add?
Enter your pool size, today’s salt reading and your cell’s target to get the pounds and bags to add. Checked against Hayward’s and Pentair’s own salt charts.
Matches Hayward’s and Pentair’s own salt charts
Answers: how many gallons is my pool?
Measure length, width and depth to get your pool’s volume in gallons and liters, then send it straight to the salt calculator.
Straight-sided oval formula, checked against Hayward’s chart
Answers: what planting zone am I in?
Your USDA hardiness zone from the official 2023 ZIP-code table, its average coldest-night range, whether it changed since the 2012 map, and your frost dates side by side.
Your USDA zone on the 2023 map, its coldest-night range and the change since 2012
Answers: when is my last frost?
Last spring and first fall frost for your ZIP at 10%, 30%, 50% and 90% odds, plus the 28°F hard-freeze dates, from the NOAA station nearest you, with its distance,…
10%, 30%, 50% and 90% odds from the NOAA station nearest you
| Your question | Tool | What you need |
|---|---|---|
| When is my last frost, and how sure is that date? | Frost dates by ZIP code | Your ZIP code |
| How many gallons does my pool hold? | Pool volume calculator | Length, width or diameter, and water depth |
| How much salt do I add to my saltwater pool? | Pool salt calculator | Gallons, today’s salt reading, your cell’s target |
| What size generator do I need? | Generator size calculator | What you want to run; your ZIP or elevation |
Looking for timing rather than a number? Our guides turn the same data into planting, lawn and pool dates for your area.
