Waterdrop says the X12 fills a six-ounce cup in about three seconds. It is a tankless under-sink reverse osmosis system. We have not lab-tested the unit.

Price at waterdropfilter.com: $1,299.00 as of Nov 4, 2026; prices change.

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Check the Waterdrop X12 price (paid link)

What Waterdrop claims

Waterdrop rates the membrane at 0.0001 micron. For microplastics and nanoplastics, the certification listings we found make no microplastics claim (no NSF/ANSI 401), so that part is the brand's word.

Waterdrop rates the X12 at 1,200 gallons per day, measured at 30 psi and 77°F, with a 3:1 pure-to-drain ratio.

What we verified

IAPMO R&T's public directory, read Nov 3, 2026, lists X12 models under NSF/ANSI 58 for TDS reduction (file WC-13976), NSF/ANSI 42 for chlorine, taste and odor on the F1A and F2 filters (WC-14301), and NSF/ANSI/CAN 372 lead-free (WC-13977). The files name model codes like WD-X12-WAQ, not every retail suffix: these listings cover X12 models.

Day-to-day use

The smart faucet knob picks 5 to 64 oz: press it and walk away while it fills. The screen shows live TDS and filter-due reminders.

There is no storage tank, and UV runs only while water flows. The mineral stage adds minerals back, so the TDS reading is higher, which the manual calls normal.

Waterdrop rates the F1 carbon filter for up to 12 months, the F2 sediment and carbon block filter for up to 6 months, and the F3 RO membrane for up to 24 months.

Three real catches

Drilling. You need a 1-inch faucet hole if the counter lacks one, plus a 1/4-inch hole in the drain pipe.
Power and setup. It needs a power outlet under the sink, and first use needs a 35-minute flush.
Cost and waste. It is among Waterdrop's priciest systems, with yearly filter costs and about one cup sent to the drain for every three made. It is also big: over 18 inches long and nearly 17 tall.

Who is it for

The X12 suits owners wanting fast tankless RO with a smart faucet. For renters, a kitchen with no outlet under the sink, or a tighter budget, a smaller system fits better.

These are affiliate links. We may earn a commission if you buy through our link. The seller fulfills the order.

Check the Waterdrop X12 price (paid link)

Specs are Waterdrop's figures, not our measurements. Images: Waterdrop.