Same water,
without the case of bottles.
Tap water costs about half a cent a gallon, so most of what you pay for bottled water is the bottle. See what a filter saves against your bottled-water habit.
Beta Water is our newest calculator and still in beta. Several equipment prices are cross-retailer estimates and may change as we verify them.
What you buy out now. Every result is measured against this.
1 Your bottled-water habit
How many bottles a day or week? Tap Edit prices to match what you pay.
2 Fine-tune upkeep
Filter cartridges are already counted per gallon above, so they are not repeated here.
Counted against your at-home cost for the whole projection.
The gear and ingredients you'd use to make it yourself.
3 Pick your filter
Your filter sets the upfront cost. Options run from a faucet mount to a countertop RO unit.
4 Your filter refills
These are the refills that fit the filter you picked above. Each one’s cost is the cartridge price spread over its rated gallons, plus about half a cent of tap water.
Your savings
Add your usual drinks above to see what you'd save.
Over 3 years, you'd keep
—
One bottle
Your money over time
Trash you never make
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Shop Long-life pitcher filter on AmazonAd-free and paid for only by Amazon affiliate links. You pay the same price either way.
Which filter pays off fastest?
Sorted fastest first, based on the habit you entered.
“Highest rated” and “Most popular” come from customer ratings at Walmart, Home Depot, Target and other retailers, checked October 2026.
Test first, then buy the right filter
A cheap TDS meter or test kit shows what your tap needs. There are also bottles to carry it and a fridge filter if that’s where you drink from.