Choosing between laser and IPL: the honest balance
Potential advantages
- Laser concentrates all of its energy at one wavelength chosen for the target, and controlled trials repeatedly put it ahead: 69.2 per cent reduction against 52.7 per cent for IPL at twelve months in one split body randomised trial
- IPL is genuinely cheaper per session and was the more comfortable of the two in that same trial, which is why plenty of clinics keep both rather than one
- Both are cleared for permanent hair reduction under exactly the same regulatory definition, so IPL is not the placebo that laser marketing sometimes implies
Limitations and trade-offs
- The published efficacy ranges overlap so heavily that phototype match, parameter choice and operator skill matter more than whether the badge on the machine says laser or IPL
- Neither technology works on white, grey, red or fine vellus hair, because there is no pigment in the shaft for the light to heat
- Regulatory efficacy endpoints stop at twelve months and no controlled durability data exist beyond that for either, so long term maintenance is an unknown rather than a promise
Walk past enough clinic windows and you will see the same treatment sold under two names as though they were interchangeable, and occasionally under a third, “IPL laser”, which is a contradiction in terms. IPL is not a laser. Both use light to heat pigmented hair until the follicle stops producing it, and both carry the same regulatory claim, but they make that light in fundamentally different ways. The difference is not marketing noise. It shows up in the trial results, on the price list, and in who each one is safe for.
Laser and IPL side by side
| Laser | IPL | |
|---|---|---|
| Light source | One coherent wavelength, typically 755 nm alexandrite, 805 nm diode or 1064 nm Nd:YAG | A filtered xenon or krypton flashlamp emitting non-coherent light across roughly 400 to 1400 nm |
| Where the energy lands | All of it at a single wavelength chosen for melanin absorption and follicle depth | Spread across a broad band, with cut-off filters stripping out the shortest wavelengths |
| Reduction in a pooled review | 30 to 73.6 per cent for Nd:YAG, 35 to 84.3 per cent for alexandrite, 32.5 to 69.2 per cent for diode | 27 to 52.7 per cent |
| Same trial, same patients, 12 months | 69.2 per cent with a diode laser | 52.7 per cent |
| Reported pain in that trial | 3.7 on a 10 point scale | 1.6 |
| Regulatory claim | Permanent hair reduction | Permanent hair reduction, identical definition |
| Usual commercial position | More per session, generally fewer of them | Cheaper per session, typically more of them |
Why “IPL laser” is a contradiction
A laser emits coherent light at one wavelength, all the waves in step. IPL does something quite different. It fires a filtered xenon or krypton flashlamp, and the MHRA’s guidance on the safe use of lasers, intense light source systems and LEDs describes that output as spanning roughly 400 to 1400 nm, against the single monochromatic lines of an alexandrite or diode laser.
That is a genuine engineering distinction, not a safety let off. A local authority safety note for salons makes the point bluntly: intense pulsed light systems are not lasers, but they can still damage the skin and eyes if misused. Protective eyewear for everyone in the room is not optional for either technology.
The physics that decides whether either works
Both rely on the same 1983 idea. Selective photothermolysis says a pigmented target can be destroyed without cooking its surroundings if three things align: a wavelength the target absorbs preferentially, enough energy to pass its damage threshold, and a pulse short enough to keep the heat in it.
Two of those are about timing. Skin sheds heat far faster than a hair follicle does. The epidermis has a thermal relaxation time of 3 to 10 milliseconds against the follicle’s 40 to 100, so a pulse pitched between the two spares the surface while the follicle stays hot enough to be damaged. Depth matters too: follicles sit anywhere from 2 to 7 mm down, and only wavelengths between 630 and 1100 nm reach the full length of an actively growing hair.
This is exactly where the two technologies separate. A laser puts every joule inside that window, at one wavelength picked for the depth of the hair and the melanin in the surrounding skin. IPL spreads the same shot across a far wider band and leans on cut-off filters to remove the shorter wavelengths that would otherwise be soaked up by the epidermis. Breadth is not a fault in itself, and it is why IPL is also used for pigmentation and redness. It does mean a smaller share of each pulse lands where it does the most useful work on hair.
What the trials actually found
A 2022 systematic review gives the widest view: hair reduction of roughly 30 to 73.6 per cent for Nd:YAG, 35 to 84.3 per cent for alexandrite, 32.5 to 69.2 per cent for diode and 27 to 52.7 per cent for IPL. The IPL band is lower, but note how much all four overlap.
Head to head studies are more useful, because they treat the same people. A split body randomised trial in the British Journal of Dermatology found 69.2 per cent reduction with a diode laser against 52.7 per cent with IPL at twelve months, with the laser scoring notably higher for pain, 3.7 against 1.6 on a 10 point scale. In Fitzpatrick IV to VI skin the gap widened: 79.4 per cent with long pulsed Nd:YAG against 54.4 per cent with IPL. A network meta-analysis of 13 randomised trials covering 652 patients ranked diode the most effective of the platforms compared. A dermatology review sums the trade off up plainly: IPL is less expensive but not as effective, and typically requires more treatment sessions even where each appointment is quicker.
The honest reading is that laser is ahead on average and clearly ahead in darker skin, but that no platform clears all the hair, and the overlap in those ranges says something important. How well the device is matched to your skin tone, how the parameters are set and who is holding the handpiece do more for your result than the word on the front of the machine.
The claim that IPL “isn’t permanent”
This one is repeated so often it has become received wisdom, and it is wrong. FDA clearance letters define the claim precisely: permanent hair reduction is a long term, stable reduction in the number of hairs regrowing measured at 6, 9 and 12 months after a course. When a consumer IPL family was cleared for over the counter sale in 2023, it carried that same wording. IPL underperforms laser in trials. It is not excluded from the claim.
The word worth holding onto is in both indications anyway, and it is reduction, not removal. The FDA describes electrolysis, not laser or IPL, as a permanent hair removal method. And “FDA cleared” settles nothing about which is better, because clearance is a substantial equivalence decision and, in the words of one peer reviewed comparison, the FDA does not assess or compare clinical efficacy or efficiency.
Skin, hair and who each one suits
Neither technology has anything to work with in a hair that carries no pigment. Both are ineffective for thin vellus hairs and white, grey or red hairs, which no device setting fixes.
Skin tone is the sharper dividing line. IPL’s broad output includes wavelengths that epidermal melanin absorbs readily, which is why consumer units are usually restricted to lighter phototypes and why the Nd:YAG figures above pull so far ahead in deeper skin. If that applies to you, our piece on wavelength choice and skin tone goes into it properly. It is also worth knowing that turning the energy down for comfort is not a neutral choice: in one retrospective cohort treated with an alexandrite laser, 5.2 per cent of patients developed paradoxical extra hair growth, with suboptimal fluence named as a risk factor.
Home IPL is a third category, not a cheaper version
The home devices sold as an alternative to a clinic course are IPL, and the gap is measurable. A cleared over the counter device operates at 1.03 to 3.08 joules per square centimetre with pulses of 4 to 12 milliseconds, where a cleared professional platform reaches up to 53 and 80 joules per square centimetre with pulses from 0.25 to 100 milliseconds. Those short pulses sit below the follicle’s 40 to 100 millisecond relaxation time, which is a physical reason, not a snobbish one, why home results are weaker.
Set the marketing against that. Consumer brands advertise 95 or 96 per cent hair reduction in weeks, while the American Academy of Dermatology tells patients to expect 10 to 25 per cent reduction after the first professional treatment. Unbranded devices bought online are riskier still: one case report describes a woman who sustained a full thickness burn after less than two minutes with a handheld device that arrived with no instructions.
What to ask before you book in Leeds
Regulation here is thinner than most people assume. For exclusively cosmetic purposes in England, practitioners using IPL or Class 3B and 4 lasers do not have to register with the Care Quality Commission, though some councils run their own registration schemes. Section 180 of the Health and Care Act 2022 created the power to license both practitioners and premises, and the Government has placed non-ablative laser and IPL in the lowest risk tier of its proposals, but the scheme is not yet in force. Until it is, the questions do the work: which wavelengths does the device emit, who assessed your skin tone, is there a test patch, and what eyewear is used.
On sessions, expect a range rather than a number. The Academy suggests 2 to 6 treatments every 4 to 6 weeks, UK clinics commonly quote 6 to 8, and a real world study of 150 patients with Fitzpatrick IV to VI skin recorded a mean of 8.9 treatments for 54.3 per cent reduction. Our article on how many sessions this really takes unpacks that spread. UK per session prices run broadly from about £35 to £300 depending on the area, with courses of six often priced as five.
If you want a straight answer about whether laser hair removal or IPL suits your skin and your hair, rather than which one a clinic happens to own, our practitioners in Leeds will assess you and tell you honestly, including when the answer is that neither will do much.
Frequently asked questions
Questions about laser hair removal.
Is IPL the same as laser hair removal?
No. A laser emits coherent light at a single wavelength. IPL uses a filtered xenon or krypton flashlamp that emits non-coherent light across a broad band, described in MHRA guidance as roughly 400 to 1400 nm. They work on the same principle, which is heating the pigment in the hair, but they are different light sources and the phrase IPL laser is a contradiction.
Which one is better, laser or IPL?
On average, laser. A split body randomised trial found 69.2 per cent hair reduction with a diode laser against 52.7 per cent with IPL at twelve months, and a trial in Fitzpatrick IV to VI skin found 79.4 per cent with long pulsed Nd:YAG against 54.4 per cent with IPL. The ranges in pooled reviews overlap a good deal though, so the match between the device, your skin tone and your hair matters more than the label.
Is IPL permanent?
It carries the same claim as laser, which is permanent hair reduction rather than permanent hair removal. The FDA defines that as a stable reduction in the number of hairs regrowing measured at 6, 9 and 12 months after a course. A consumer IPL family cleared in 2023 uses exactly that wording. The FDA reserves the term permanent hair removal for electrolysis, not for laser or IPL.
Does laser hurt more than IPL?
In the one randomised trial that measured both on the same patients, yes. Diode laser scored 3.7 on a 10 point pain scale against 1.6 for IPL. The American Academy of Dermatology likens laser pulses to warm pinpricks or a rubber band snapped against the skin. Turning the energy down to make it comfortable is not a free choice, because under dosing is a documented risk factor for stimulating hair growth rather than reducing it.
Can I just buy a home IPL device instead?
You can, but it is a different category of treatment. A cleared over the counter IPL device runs at 1.03 to 3.08 joules per square centimetre, where a cleared professional laser reaches up to 53 or 80. Home devices are best thought of as a maintenance and mild reduction tool for lighter skin with dark hair, not a substitute for a clinical course.
