OVERALL

SPECS

VS AVERAGE

REVIEWS

ALTERNATIVES

Dreo Humidifier HM311 4L Review | 43 Data compared

Avg. price in UK: ~£45
Avg. price in US: ~$40
Humidification rate: 250 ml/h
Maximum room area: 27.87 m²
Water tank capacity: 4 L
Maximum operating time: 36 hours
Maximum noise level: 32 dB

Dreo Humidifier HM311 4L review. Compare 43 technical specifications and user reviews to see how this product ranks in the Humidifiers category and whether it is worth buying.

7.0

Very good

6.4

Good

9.2

Exceptional

7.3
Bedroom use
Score components:
35.0%
7.5
Maximum noise level
25.0%
7.4
Maximum operating time
20.0%
4.0
Timer
20.0%
10
Automatic low-water shut-off
5.6
Large rooms
Score components:
35.0%
6.1
Humidification rate
30.0%
4.4
Maximum room area
25.0%
6.8
Water tank capacity
10.0%
4.0
Hygrostat
5.2
Plant care
Score components:
30.0%
4.0
Hygrostat
25.0%
6.1
Humidification rate
25.0%
6.8
Water tank capacity
20.0%
4.0
360° nozzle

Best prices in UK

Best rankings

Verdict

The Dreo Humidifier HM311 is a 26-watt ultrasonic cool mist humidifier featuring a 4-liter water tank, a 28 dB ultra-quiet noise rating, and an effective coverage range of up to 300 square feet. Key characteristics and pros include its 3-in-1 design combining a humidifier, an essential oil aroma diffuser pad, and an integrated nightlight, alongside a 4-inch wide mist outlet that shoots a 5μm ultrafine mist up to 40 inches high for a continuous runtime of 32 to 36 hours. Its convenient touch-controlled, top-fill modular design makes it remarkably easy to clean and refill without spilling water; however, notable cons include its loose, non-locking lid that can easily be knocked off, a lack of an included demineralization cartridge which can cause white dust when using hard water, and a power output that can feel slightly underpowered for larger spaces.

Technical Specifications of humidifier Dreo Humidifier HM311 4L

Overall score

7.0

Show more

Hide

Popularity

What it is: An indicator based on the number of reviews received by products in the Humidifiers category.

When it matters: When you prefer products in the Humidifiers category that have been chosen and reviewed by many other buyers.

Performance

6.4

Show more

Hide

Technology

What it is: The method the humidifier uses to turn water into moisture for the room.

When it matters: Technology affects mist temperature, visible output, maintenance needs, and sensitivity to minerals in the water.

Importance: LOW

ultrasonic

Humidification rate

What it is: The maximum amount of water the humidifier can release into the air per hour.

When it matters: A higher rate raises room humidity faster and is more useful in dry or larger spaces.

Importance: HIGH

Good value: At least 300 ml/h

Maximum room area

What it is: The largest room floor area the humidifier is recommended to cover.

When it matters: A larger coverage rating is important for open-plan spaces and larger bedrooms or living rooms.

Importance: HIGH

Good value: At least 40 m²

Water tank capacity

What it is: The usable amount of water the humidifier’s reservoir can hold.

When it matters: A larger tank generally needs fewer refills and can support longer operation between top-ups.

Importance: HIGH

Good value: At least 4 L

Maximum operating time

What it is: The longest stated operating time from one full water tank.

When it matters: Longer runtime means fewer refills during overnight use or extended daily operation.

Importance: HIGH

Good value: At least 24 hours

Show more

Features

6.5

Show more

Hide

Warm mist function

What it is: Indicates whether the humidifier can produce warm mist as well as cool mist.

When it matters: Useful when you want warmer output in cool weather instead of cool mist alone.

Importance: HIGH

Good value: yes

Aromatherapy support

What it is: Indicates whether the humidifier supports the safe use of aromatic oils or fragrance media.

When it matters: Useful if you want to add fragrance without putting oil directly into the water tank.

Importance: MEDIUM

Good value: yes

Dedicated aroma compartment

What it is: Indicates whether the humidifier has a separate compartment for aroma pads or essential oils.

When it matters: A dedicated compartment keeps fragrance media separate from the main water tank.

Importance: LOW

Good value: yes

Automatic low-water shut-off

What it is: Indicates whether the humidifier switches itself off when the water level becomes too low.

When it matters: This safety feature helps prevent the unit from continuing to run with an empty tank.

Importance: HIGH

Good value: yes

Water level indicator

What it is: Indicates whether the humidifier shows the amount of water remaining in its tank.

When it matters: A visible level indicator makes it easier to know when the tank needs refilling.

Importance: MEDIUM

Good value: yes

Show more

Design

6.2

Show more

Hide

Fill type

What it is: The design mechanism used to add water to the humidifier tank, distinguished primarily between convenient top-fill and inverted bottom-fill designs.

When it matters: Top-fill humidifiers let you pour water directly into the top with a pitcher without carrying a heavy, dripping tank to the tap.

Importance: LOW

top fill

Color

What it is: The primary exterior color of the humidifier.

When it matters: Color matters when you want the humidifier to blend with the room.

Importance: LOW

black

Material

What it is: The primary material used for the humidifier’s exterior housing.

When it matters: Material matters for durability, feel and appearance.

Importance: LOW

plastic

360° nozzle

What it is: Whether the humidifier has a nozzle that rotates through 360° to direct the mist.

When it matters: A rotating nozzle helps redirect mist without moving the humidifier.

Importance: LOW

Good value: yes

Display

What it is: Whether the humidifier has a display for settings and status information.

When it matters: A display makes humidity, mode and timer information easier to check.

Importance: LOW

Good value: yes

Show more

Dreo Humidifier HM311 4L vs the average humidifier

Why is Dreo Humidifier HM311 4L better than the average humidifier?

Show more

Hide

Dedicated aroma compartment
Dreo Humidifier HM311 4L includes a dedicated aroma compartment; the average humidifier does not include a dedicated aroma compartment.
Includes dedicated aroma hardware such as a tray, pad, drawer, or compartment.
What it is: Indicates whether the humidifier has a separate compartment for aroma pads or essential oils.
When it matters: A dedicated compartment keeps fragrance media separate from the main water tank.
Importance: LOW
Good value: yes
Dreo Humidifier HM311 4L includes a dedicated aroma compartment; the average humidifier does not include a dedicated aroma compartment.
12 hours longer runtime
Dreo Humidifier HM311 4L runs longer on a single fill than the average humidifier (36 hours vs 24 hours).
What it is: The longest stated operating time from one full water tank.
When it matters: Longer runtime means fewer refills during overnight use or extended daily operation.
Importance: HIGH
Good value: At least 24 hours
Dreo Humidifier HM311 4L runs longer on a single fill than the average humidifier (36 hours vs 24 hours).36 hours vs 24 hours
4.25 cm shallower body
Dreo Humidifier HM311 4L has a shallower depth than the average humidifier (14 cm vs 18.25 cm).
What it is: The humidifier’s front-to-back depth.
When it matters: A shallower humidifier needs less usable surface depth on a table or shelf.
Importance: MEDIUM
Good value: Up to 20 cm
Dreo Humidifier HM311 4L has a shallower depth than the average humidifier (14 cm vs 18.25 cm).14 cm vs 18.25 cm
0.65 L larger water tank
Dreo Humidifier HM311 4L has a larger water tank than the average humidifier (4 L vs 3.35 L).
What it is: The usable amount of water the humidifier’s reservoir can hold.
When it matters: A larger tank generally needs fewer refills and can support longer operation between top-ups.
Importance: HIGH
Good value: At least 4 L
Dreo Humidifier HM311 4L has a larger water tank than the average humidifier (4 L vs 3.35 L).4 L vs 3.35 L
3.18 cm shorter body
Dreo Humidifier HM311 4L has a lower profile than the average humidifier (25.8 cm vs 28.98 cm).
What it is: The humidifier’s total height from its base to its highest point.
When it matters: A shorter humidifier fits more easily beneath shelves and in low spaces.
Importance: LOW
Good value: Up to 25 cm
Dreo Humidifier HM311 4L has a lower profile than the average humidifier (25.8 cm vs 28.98 cm).25.8 cm vs 28.98 cm
14.5% higher user score
Dreo Humidifier HM311 4L has a higher user score than the average humidifier (9.16 vs 8).
What it is: A rating that combines user reviews with the total review volume for products in the Humidifiers category.
When it matters: When you want to know how products in the Humidifiers category perform in everyday use and how reliable owners find them over time.
Dreo Humidifier HM311 4L has a higher user score than the average humidifier (9.16 vs 8).9.16 vs 8
1.1 dB lower maximum noise
Dreo Humidifier HM311 4L is quieter at maximum output than the average humidifier (32 dB vs 33.1 dB).
What it is: The highest stated operating sound level across normal humidification modes.
When it matters: A lower maximum noise level is better for bedrooms, nurseries, calls, and light sleepers.
Importance: HIGH
Good value: Up to 35 dB
Dreo Humidifier HM311 4L is quieter at maximum output than the average humidifier (32 dB vs 33.1 dB).32 dB vs 33.1 dB
80.7% more popular
Dreo Humidifier HM311 4L is more popular than the average humidifier (10 vs 5.535).
What it is: An indicator based on the number of reviews received by products in the Humidifiers category.
When it matters: When you prefer products in the Humidifiers category that have been chosen and reviewed by many other buyers.
Dreo Humidifier HM311 4L is more popular than the average humidifier (10 vs 5.535).10 vs 5.54
12 hours longer runtime
Dreo Humidifier HM311 4L runs longer on a single fill than the average humidifier (36 hours vs 24 hours).
0.65 L larger water tank
Dreo Humidifier HM311 4L has a larger water tank than the average humidifier (4 L vs 3.35 L).
1.1 dB lower maximum noise
Dreo Humidifier HM311 4L is quieter at maximum output than the average humidifier (32 dB vs 33.1 dB).
Dedicated aroma compartment
Dreo Humidifier HM311 4L includes a dedicated aroma compartment; the average humidifier does not include a dedicated aroma compartment.
4.25 cm shallower body
Dreo Humidifier HM311 4L has a shallower depth than the average humidifier (14 cm vs 18.25 cm).
3.18 cm shorter body
Dreo Humidifier HM311 4L has a lower profile than the average humidifier (25.8 cm vs 28.98 cm).
4.7% lighter
Dreo Humidifier HM311 4L is lighter than the average humidifier (1.4 kg vs 1.48 kg).

Why is Dreo Humidifier HM311 4L worse than the average humidifier?

Show more

Hide

3.13 m² less room coverage
Dreo Humidifier HM311 4L covers smaller rooms than the average humidifier (27.9 m² vs 31 m²).
2 W higher power draw
Dreo Humidifier HM311 4L draws more power than the average humidifier (26 W vs 24 W).
3.8% lower humidification rate
Dreo Humidifier HM311 4L delivers a lower humidification rate than the average humidifier (250 ml/h vs 260 ml/h).
No timer
Dreo Humidifier HM311 4L does not include a programmable timer; the average humidifier includes a programmable timer.
8.45 cm wider body
Dreo Humidifier HM311 4L has a wider body than the average humidifier (28 cm vs 19.555 cm).
No 360° nozzle
Dreo Humidifier HM311 4L does not have a 360° nozzle; the average humidifier has a 360° nozzle.
0.01 m shorter power cable
Dreo Humidifier HM311 4L has a shorter power cable than the average humidifier (1.5 m vs 1.51 m).
No timer
Dreo Humidifier HM311 4L does not include a programmable timer; the average humidifier includes a programmable timer.
What it is: Indicates whether the humidifier includes a timer for scheduled operation or shut-off.
When it matters: A timer helps you limit overnight runtime or arrange operation around your routine.
Importance: HIGH
Good value: yes
Dreo Humidifier HM311 4L does not include a programmable timer; the average humidifier includes a programmable timer.
8.45 cm wider body
Dreo Humidifier HM311 4L has a wider body than the average humidifier (28 cm vs 19.555 cm).
What it is: The humidifier’s side-to-side width.
When it matters: A narrower humidifier takes up less space on a bedside table, desk or shelf.
Importance: MEDIUM
Good value: Up to 20 cm
Dreo Humidifier HM311 4L has a wider body than the average humidifier (28 cm vs 19.555 cm).28 cm vs 19.555 cm
No 360° nozzle
Dreo Humidifier HM311 4L does not have a 360° nozzle; the average humidifier has a 360° nozzle.
What it is: Whether the humidifier has a nozzle that rotates through 360° to direct the mist.
When it matters: A rotating nozzle helps redirect mist without moving the humidifier.
Importance: LOW
Good value: yes
Dreo Humidifier HM311 4L does not have a 360° nozzle; the average humidifier has a 360° nozzle.
3.13 m² less room coverage
Dreo Humidifier HM311 4L covers smaller rooms than the average humidifier (27.9 m² vs 31 m²).
What it is: The largest room floor area the humidifier is recommended to cover.
When it matters: A larger coverage rating is important for open-plan spaces and larger bedrooms or living rooms.
Importance: HIGH
Good value: At least 40 m²
Dreo Humidifier HM311 4L covers smaller rooms than the average humidifier (27.9 m² vs 31 m²).27.87 m² vs 31 m²
2 W higher power draw
Dreo Humidifier HM311 4L draws more power than the average humidifier (26 W vs 24 W).
What it is: The humidifier’s maximum rated electrical power draw.
When it matters: Lower power draw can reduce electricity use, especially when the humidifier runs for many hours each day.
Importance: MEDIUM
Good value: Up to 25 W
Dreo Humidifier HM311 4L draws more power than the average humidifier (26 W vs 24 W).26 W vs 24 W
0.01 m shorter power cable
Dreo Humidifier HM311 4L has a shorter power cable than the average humidifier (1.5 m vs 1.51 m).
What it is: The usable length of the humidifier’s power cable.
When it matters: A longer cable offers more freedom to place the humidifier away from a wall socket.
Importance: LOW
Good value: At least 1.5 m
Dreo Humidifier HM311 4L has a shorter power cable than the average humidifier (1.5 m vs 1.51 m).1.5 m vs 1.51 m
3.8% lower humidification rate
Dreo Humidifier HM311 4L delivers a lower humidification rate than the average humidifier (250 ml/h vs 260 ml/h).
What it is: The maximum amount of water the humidifier can release into the air per hour.
When it matters: A higher rate raises room humidity faster and is more useful in dry or larger spaces.
Importance: HIGH
Good value: At least 300 ml/h
Dreo Humidifier HM311 4L delivers a lower humidification rate than the average humidifier (250 ml/h vs 260 ml/h).250 ml/h vs 260 ml/h
28.6% more expensive
Dreo Humidifier HM311 4L is more expensive than the average humidifier (£45 vs £35).
Dreo Humidifier HM311 4L is more expensive than the average humidifier (£45 vs £35).£45 vs £35

Graphic comparison of Dreo Humidifier HM311 4L and other products in the Humidifiers category

Attribute category

Attribute

No results found

Third-party reviews

United Kingdom

United States

(Reviews last updated: August 2026)

What customers like about Dreo Humidifier HM311 4L?

Generates a powerful, fine mist that spreads evenly without wetting surrounding furniture.
Operates very quietly at around 28dB, making it excellent for bedrooms and nurseries.
Large 4-liter capacity provides an impressive runtime of up to 32 to 36 hours on low settings.
Convenient top-fill design simplifies water refills and eliminates messy spills.
Modular parts and wide opening make the water tank easy to detach and clean.
Features a built-in aroma pad for essential oils and a dual-purpose soothing ambient nightlight.

What customers dislike about Dreo Humidifier HM311 4L?

The top lid sits loosely on the unit and does not lock, making it prone to being knocked off easily.
Lacks a dedicated water level indicator light on the base model to view remaining water in the dark.
Prone to pink mold and mineral residue if not cleaned frequently every few days.
Can leave white dust on surfaces if operated using hard tap water instead of distilled water.
The base model (HM311) lacks a built-in automatic humidity sensor and Wi-Fi smart app integration.

Expert reviews

techgearlab.com

19/08/2025

Summary of the review

Dreo HM311 Review | Tested & Rated - TechGearLab

The Dreo HM311 is recognized by TechGearLab as a top budget-friendly humidifier, praised for its straightforward operation, intuitive interface, and remarkably low power consumption, while offering an easy-to-clean, top-fill design. However, the review highlights significant drawbacks, including a constant 41dB dripping sound, less powerful humidification compared to top competitors, and a strict requirement for demineralized water to prevent white dust.

haus-garten-test.de

04. Dezember 2025

Summary of the review

DREO Humidifier 311S Review – Smart with App Control

The DREO 311S Smart Humidifier is praised by Haus & Garten Test for its user-friendly, tool-free setup and efficient 4-liter top-fill design. Key advantages include smart app integration for real-time tracking, low energy consumption, and an automatic shutdown feature, though a notable drawback is the lack of an included demineralization cartridge for hard water areas.

homeandsmart.de

06. Dezember 2024

Summary of the review

Dreo Humidifier Review – Top Ultrasonic Humidifiers for Your Smart Home

The Dreo Smart Humidifier, as reviewed by home&smart, is a quiet, budget-friendly, and highly effective unit designed for small to cozy bedrooms up to 27 square meters. Key pros include strong, consistent performance, smart app control, a decorative RGB light, and a convenient top-fill design. The primary cons are its limited coverage area, making it unsuitable for larger rooms, and the recommendation to use distilled water to avoid mineral buildup.

electroworldlyon.fr

19/08/2025

Summary of the review

Dreo HM311 Humidifier at Electro World

The Dreo HM311, featured on Electro World Lyon, is an ultrasonic cool mist humidifier designed for quiet operation in rooms and nurseries, boasting a 4-litre capacity and easy top-fill design. While praised for preventing wet furniture with fine atomization, the unit lacks an automatic relative humidity sensor for self-regulation, requiring manual control, and possesses a large footprint.

techgearlab.com

19/08/2025

Summary of the review

The Best Humidifiers | Lab Tested and Ranked

TechGearLab's comprehensive evaluation of 14 humidifiers identified the Levoit OasisMist 450S Smart as the top pick for its powerful dual-mist performance and intuitive app, despite its high energy consumption, frequent refilling needs, and difficult cleaning around the boiling plate. Other notable options included the high-capacity Levoit Classic 300S, the budget-friendly Dreo HM311, and the large-room focused Levoit LV600S, which provides fast, significant moisture output but operates loudly, while the evaporative Blueair InvisibleMist H35i offers efficiency with tap water.

Video reviews

Best alternatives

Humidifiers

GoveeLife Smart 4.5L

Humidifiers

Dreo Smart Humidifier HM306S 3L

Humidifiers

Xiaomi Mi Smart Humidifier 2

Humidifiers

LEVOIT Dual 150

Humidifiers

Olimpia Splendid Limpia 6

Humidifiers

Dreo Smart Humidifier HM524S 6L

Humidifiers

Medisana AH 661

Humidifiers

CONOPU OZJ21S07

Humidifiers

LEVOIT Classic 300S

Humidifiers

Humidifiers

Humidifiers

Compare Dreo Humidifier HM311 4L with other products in the Humidifiers category

Compare