Waterdrop vs LG: which is actually certified — and what does a certified gallon cost?

Last reviewed July 2026.

Same job, same shelf — but the certifications underneath are not the same. Here is Waterdrop against LG on the only two axes we score: what the certification actually covers, and what a certified gallon costs.

• Waterdrop: cheapest certified-for-lead filter is the WDS-F27 at $0.030/certified gallon (NSF, NSF/ANSI 42, 53).
• LG: cheapest certified-for-lead filter is the LT1000P at $0.275/certified gallon (NSF, NSF/ANSI 42, 53, 401).

On certified-for-lead cost per gallon, Waterdrop wins: $0.030 vs $0.275 — 9.2× cheaper for every gallon its certification covers.

Every model, side by side

Price per filter ÷ certified capacity in gallons. Certification data from the certifiers' public listings; the listing always wins.

The full stories: Is Waterdrop NSF certified? · Is LG NSF certified? · what 42, 53 and 401 mean

We do not test filters — we index what accredited certifiers publish, with attribution, and make no health or treatment claims. A certification covers a specific model against a specific standard; it is not a general seal of quality. We are not affiliated with NSF International.