Best Dreo Humidifier for Days Between Refills: 6L to 11L Compared

By Simone Ellery · Updated 2026-10-25T02:55:07.277Z · How we choose · How we make money

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Smart Humidifier 713S 6L

$89.99 90-day range $89.99 – $89.99 trend: flat Lowest price in 90 days

Pros

• 6 L tank for long runs between refills
• Quiet operation at 28 dB
• Rated 4.8 by users
• Lowest-priced model here at $89.99, $30 less than the 717S 8L

Cons

• Smallest tank in the lineup, so shorter runtime than the 8 L and 11 L models
• No rated coverage area or runtime listed

Who it's for: Buyers who want a quiet, well-rated smart humidifier with a 6 L tank at the lowest price in the lineup.

Check price at dreo.com

Smart Humidifier 717S 8L

$119.99 90-day range $119.99 – $119.99 trend: flat Lowest price in 90 days

Pros

• 8 L tank runs up to 80 hours between refills
• Covers up to 600 sq. ft.
• Quiet at 28 dB
• Rated 4.9

Cons

• At $119.99 it costs $30.00 more than the 6 L 713S
• 6.9 lb and 14.45 in tall, heavier and taller than the 6 L model

Who it's for: Anyone wanting a large-tank smart humidifier that runs for days between refills across a 600 sq. ft. room.

Check price at dreo.com

Smart Humidifier 735S 11L

$139.99 90-day range $139.99 – $139.99 trend: flat Lowest price in 90 days

Pros

• 11 L tank is the largest in the lineup, with a 100-hour runtime between refills
• 26 dB is quieter than the 713S, 717S and 774S
• 4.9 rating
• At $139.99 it's $20.00 more than the 717S 8L and $20.00 less than the 774S 10L

Cons

• 30.91-inch height makes it the tallest of the group, so placement is less flexible
• $139.99 is $50.00 more than the 713S 6L

Who it's for: Anyone who wants the longest run between refills and near-silent operation and has the vertical room for a tall unit.

Check price at dreo.com

Smart Humidifier 747S

$119.99 90-day range $119.99 – $119.99 trend: flat Lowest price in 90 days

Pros

• 21 dB noise rating is the quietest among the listed Dreo humidifiers
• Covers up to 700 square feet, the largest floor area listed
• Priced at $119.99, the same as the 717S 8L and $20.00 less than the 735S 11L

Cons

• No tank capacity or runtime listed, so refill interval is unclear
• No customer rating listed

Who it's for: Anyone wanting a very quiet smart humidifier for a large room up to 700 square feet who doesn't need a stated tank size.

Check price at dreo.com

Smart Humidifier 774S 10L

$159.99 90-day range $159.99 – $159.99 trend: flat Lowest price in 90 days

Check price at dreo.com

How we chose

We started with tank size, because that is what decides how long a humidifier goes between fills. The 735S 11L holds 11 L and is rated for 100 H of runtime, the largest tank and the longest runtime in the lineup. The 717S 8L holds 8 L and is rated for 80 Hours, and it covers 600 sq. ft. The 774S 10L holds 10 L. The 713S 6L holds 6 L.

Noise mattered too, since these run overnight. The 747S is listed at 21 dB, the 735S at 26 dB, the 713S and 717S at 28 dB, and the 774S at 32 dB.

On price, the 713S 6L is $89.99. The 717S 8L and the 747S are both $119.99, which is $30.00 more than the 713S. The 735S 11L is $139.99, $20.00 more than the 717S and $50.00 more than the 713S. The 774S 10L is $159.99, $20.00 more than the 735S and $70.00 more than the 713S. Each of these prices is at its 90-day low and has held flat over that period.

We favored capacity for multi-day use, so the 11 L tank and 100 H runtime carried the most weight, with noise and price as the tiebreakers.

Who should skip these

If you're humidifying well beyond 600–700 sq. ft., skip this family. The 717S 8L lists coverage of 600 sq. ft. and the 747S covers 700 sq. ft.; the 713S 6L, 735S 11L and 774S 10L don't list a coverage figure, so we can't point you to one of them for a larger room.

If you want to spend under $90, look elsewhere too. The least expensive model here is the 713S 6L at $89.99, which is $30.00 less than the 717S 8L and $50.00 less than the 735S 11L. The 717S 8L and 747S both cost $119.99, the 735S 11L is $139.99, and the 774S 10L is $159.99 — $70.00 more than the 713S 6L.

Every model is at its 90-day low, and each price has held flat over that period.

How to choose the right one

Start with the tank and the runtime, because those two numbers decide how often you refill. The 735S 11L holds 11 L and runs 100 H, the largest tank and longest runtime here, at $139.99. The 717S 8L runs 80 Hours on an 8 L tank for $119.99, which is $20.00 less than the 735S. The 774S 10L holds 10 L at $159.99, $20.00 more than the 735S, and the 713S 6L is the smallest tank at $89.99, $50.00 less than the 735S.

Then check noise and coverage against the room. The 747S is rated at 21 dB and covers 700 Square Feet for $119.99, the same price as the 717S 8L. The 735S 11L is rated at 26 dB, the 717S 8L and 713S 6L at 28 dB, and the 774S 10L at 32 dB. The 717S 8L lists 600 sq. ft. of coverage.

If you want the fewest refills, the 735S 11L is the one to compare against. If quiet operation in a larger room matters more, the 747S is $20.00 less than the 735S.

Questions readers ask

By Simone Ellery · Published 2026-09-24 · Updated 2026-10-25