Dyson Supersonic Review

Set aside the design and the price for a moment. This is the only dryer on the market that tells you exactly how hot each setting is.

By Scooter M.Published September 7, 2026Last updated September 7, 2026

A premium hair dryer photographed in a studio

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Almost every hair dryer sold has three heat settings labeled with dots, bars or the words low, medium and high. Not one of those labels tells you a temperature, which means you cannot compare two dryers on the specification that decides whether they damage your hair.

The Supersonic publishes 212F, 176F, 140F and constant cold. That is the single most useful thing about it and it is the reason it appears on more pages of this site than any other dryer.

Quick picks

Ranked, with the reasoning underneath. Tap any row to jump to that write-up; tap the price to check it on Amazon. Prices come from the live layer, never from this page.

#	Product	Best for	Type	Price
1	No photoDyson Supersonic Hair DryerThe one dryer that tells you what each heat setting actually is in degrees, which makes it the only one in the category you can plan a routine around.	Published temperatures on every heat setting	1,600W dryer	Check price#ad
2	No photoShark SpeedStyle High-Velocity Dryer (HD332)The only mainstream dryer that publishes the number that matters: it never exceeds 230F, which is below every damage threshold in the literature.	A published temperature ceiling you can actually check	High-velocity dryer	Check price#ad

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#1 · Published temperatures on every heat setting

Dyson Supersonic Hair Dryer

The one dryer that tells you what each heat setting actually is in degrees, which makes it the only one in the category you can plan a routine around.

Published specifications for the Dyson Supersonic Hair Dryer, each linked to its source
Power	1,600W at full powersource
Heat settings	4 settings — 212F (100C), 176F (80C), 140F (60C), and constant coldsource
Speed settings	3 — fast drying, regular drying, gentle dryingsource
Airflow	Up to 41 liters per secondsource
Heat regulation	Measures air temperature over 40 times a secondsource
Dimensions	9.6 in long, 3.9 in wide, 3.1 in deepsource

What those numbers mean

Four heat settings published as 212F, 176F and 140F plus cold is the disclosure the rest of the category refuses to make. It means you can pick a setting against a damage threshold instead of against a vague label.

Note where those numbers sit. Even the hottest setting, 212F, is below the 302F figure Shark names as its damage line and far below the temperatures at which the literature reports cuticle degradation.

1,600W is less nominal power than a US 1,875W dryer, and 41 l/s of airflow is how it compensates. Again: air speed, not temperature.

What it does well

Publishes an actual temperature for every heat setting, uniquely in this category
Airflow figure published in liters per second
Top setting of 212F is below every damage threshold in the cited research
Attachments attach magnetically and can be changed mid-dry

What it does not

Costs several times what a competent 1,875W dryer costs
1,600W nominal will feel slower than an AC dryer on very thick hair
Dyson does not sell through every retailer, so availability moves around

Skip this one if: Skip it if the budget is the constraint rather than the information. Everything the Supersonic does for hair health can be approximated by running a cheaper dryer on medium heat and high speed, which costs nothing.

Check price on Amazon

#ad · how this is funded

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#2 · A published temperature ceiling you can actually check

Shark SpeedStyle High-Velocity Dryer (HD332)

The only mainstream dryer that publishes the number that matters: it never exceeds 230F, which is below every damage threshold in the literature.

Published specifications for the Shark SpeedStyle High-Velocity Dryer (HD332), each linked to its source
Settings	4 heat and 3 airflow settings, plus a cool shotsource
Temperature ceiling	Measures and regulates temperature 1,000 times a second, never exceeding 230F, and never approaching 302Fsource
Weight	1.69 lbsource
In the box (HD332)	DeFrizzFast diffuser, QuickSmooth brush, RapidGloss finishersource

What those numbers mean

A stated ceiling of 230F is the single most useful specification on any dryer, and almost nobody publishes one. It puts the airflow well under the 302F figure Shark itself names as the damage line and far under the cuticle-degradation range in the research.

Compare that with the usual disclosure. Most dryers publish wattage and a number of heat settings and never say what those settings actually reach, which makes the whole category impossible to compare on the axis that matters for damage.

The RapidGloss finisher is a separate attachment for flyaways on already-dry hair, not a drying head. Treat it as a finishing step, not a reason to buy.

What it does well

Publishes an actual temperature ceiling instead of only a heat-setting count
Diffuser and brush included, so a curly routine needs nothing extra
Regulates 1,000 times a second, the same control loop as the FlexStyle

What it does not

Shark does not publish a wattage figure for the HD332
At 1.69 lb it is heavier than the FlexStyle it sits beside
The low ceiling is the point, and it does mean a slower dry than a hot 1,875W dryer

Skip this one if: Skip it if you want maximum heat for a fast, poker-straight blowout on coarse hair. The ceiling that protects fragile hair is the same ceiling that will frustrate you here.

Check price on Amazon

#ad · how this is funded

Every published specification

What Dyson publishes about the Supersonic
Specification	Published figure
Power	1,600W at full power
Heat settings	212F (100C), 176F (80C), 140F (60C), and constant cold
Speed settings	Three — fast drying, regular drying, gentle drying
Airflow	Up to 41 liters per second
Heat regulation	Measures air temperature over 40 times a second
Dimensions	9.6 in long, 3.9 in wide, 3.1 in deep

Airflow published in liters per second is the second unusual disclosure here. It is the figure that explains how a 1,600W dryer competes with 1,875W ones: it dries by moving a large volume of air rather than by heating a smaller volume more.

What 212F means against the research

Published research on thermally treated hair reports cuticle degradation beginning around 150C (302F) and cortex damage from around 200C (392F). The Supersonic's hottest setting is 212F — a hundred degrees below the first threshold.

That reframes the usual concern about blow drying. Whatever damage a Supersonic does is not thermal denaturation of keratin; it is the mechanical effect of air on the cuticle, which is addressed by lower speeds and better technique rather than by lower heat. The heat damage guide covers the difference.

The running-cost arithmetic

What one blow dry costs on the Supersonic

cost = (watts / 1000) x hours x rate per kWh

(1600 / 1000) x 0.17 h x $0.1834 = about $0.05 per 10-minute dry

Using the US average residential rate of 18.34 cents per kilowatt-hour reported by the EIA for June 2026. Roughly 5 cents a session, or about $18 a year for daily use — which is to say the electricity is never the interesting part of this purchase. Full working in what a blow dry costs to run.

What the specs do not cover

Which attachments are in the box. This varies by configuration, and some bundles include a diffuser while others do not. Check before buying if you have curls.
Durability. No manufacturer publishes a lifespan and we are not going to estimate one.
Noise. Dyson does not publish a decibel figure for the Supersonic, though Laifen does for the Swift.
Whether it feels worth it. That is a judgment about money, and the spec sheet cannot settle it.

Who should skip it

Skip it if budget is the constraint rather than the information. Everything the Supersonic does for hair health can be approximated by running a cheaper dryer on medium heat and high speed. That costs nothing, and the Shark SpeedStyle publishes a 230F ceiling for considerably less.

Skip it if you have very thick hair and want the fastest possible dry. 1,600W is real but it is below the 1,875W and 2,000W tools on the thick hair page, and airflow only partly compensates on genuinely dense hair.

The verdict

The Supersonic is the best-documented dryer in the category and the disclosure is not a marketing exercise — it lets you style against a threshold rather than against a guess. Whether that documentation and the engineering behind it justify the price against a Shark that also publishes a ceiling is a money question, and we will not pretend the specification sheet answers it for you.

Questions people actually ask

Is the Dyson Supersonic worth the money?

It is the only dryer that publishes an actual temperature for every heat setting — 212F, 176F, 140F and cold — plus an airflow figure in liters per second. If you are trying to style around a damage threshold rather than trusting an unlabeled dial, that disclosure is genuinely valuable. Whether it is worth the gap over a Shark SpeedStyle that also publishes a ceiling is a judgment about money.

How hot does the Dyson Supersonic get?

Dyson publishes four settings: 212F (100C), 176F (80C), 140F (60C) and constant cold, with air temperature measured over 40 times a second. The hottest setting is 212F, which is around a hundred degrees below the roughly 302F at which published research reports cuticle degradation beginning.

How much does it cost to run a Dyson Supersonic?

At 1,600W and the US average residential rate of 18.34 cents per kilowatt-hour reported by the EIA for June 2026, a ten-minute dry costs roughly 5 cents — about $18 a year for daily use. The electricity is never the significant cost of owning one of these.

Is the Dyson Supersonic good for thick hair?

It works, but it is not the fastest option. At 1,600W it sits below the 1,875W and 2,000W dryers on our thick hair page, and while its 41 liters per second of airflow compensates substantially, on genuinely dense hair a powerful AC dryer will finish sooner. Its advantage is heat control rather than raw drying speed.

Sources

Every figure on this page traces to one of these. If a number here disagrees with the manufacturer, the manufacturer is right and we want to know — tell us.