You can often recover a shrunken garment — partially. Anyone promising full restoration is overselling it, so here's the honest version. Soaking in lukewarm water with hair conditioner relaxes the fibres enough to stretch a garment back out, and it works reasonably well on cotton and wool — but expect partial recovery, not a return to original size.
Why it works at all (the honest mechanism)
Understanding this sets realistic expectations. Shrinkage happens when heat and agitation cause tensioned fibres to contract and, in the case of wool, to interlock. The unshrinking method works by relaxing those fibres — conditioner or a similar agent lubricates and softens them, and gentle physical stretching while wet coaxes them back toward their original length. Critically, you're not undoing damage, you're temporarily making the fibres pliable enough to reposition. That's why results are partial and why the effect can partly reverse over subsequent washes if you go back to hot water and high heat.
The method (step by step)
The standard approach, which is genuinely worth trying. 1. Fill a basin with lukewarm water — not hot; heat is what caused the problem. 2. Add a couple of tablespoons of hair conditioner (baby shampoo or wool detergent also work) and mix until dispersed. 3. Submerge the garment and soak for around 30 minutes, gently working the solution through. 4. Remove without rinsing, and squeeze out excess water gently — don't wring, which distorts the shape. 5. Lay it on a towel, roll the towel to absorb more water. 6. Gently stretch the garment to the desired dimensions, working outward from the centre. 7. Lay flat to dry, re-stretching periodically as it dries.
What fabrics it works on
Honest expectations by material. Wool and cashmere — the method works best here, since wool fibres respond well to conditioning agents; this is where it originated. Cotton — works reasonably well; cotton stretches back somewhat with patience. Cotton blends — partial results, proportional to the natural fibre content. Synthetics (polyester, nylon) — largely won't respond, but they also barely shrink in the first place, so if a synthetic garment has changed size, something else happened (usually heat damage, which isn't recoverable). Anything felted — if wool has genuinely felted into a dense, stiff mat, that change is essentially permanent; interlocked fibres don't separate.
Be honest about the results
The part most guides skip. Expect partial recovery — often getting back a portion of what was lost rather than the full original dimensions. A garment that shrank a full size might come back most of a size, or might not. Two further honest points: the recovery isn't always even, so you can end up with a garment that's stretched more in one dimension than another and looks slightly off; and results can partly regress if the garment goes back through hot washing. Realistic framing: this is a rescue attempt with decent odds, not a reliable restoration. If the garment is badly shrunken, manage your expectations before you invest an afternoon.
When a garment is genuinely gone
Knowing when to stop is useful. A garment is likely unrecoverable if: wool has felted into a stiff, dense fabric with no visible knit structure; synthetic fibres have been heat-damaged — melted, glazed, or gone hard and shiny; the item shrank dramatically rather than moderately; or the shape has distorted as well as reduced, with twisted seams or an uneven hem. In those cases the honest answer is that it's done. The realistic remaining options are giving it to someone smaller, repurposing the fabric, or replacing it — and accepting that beats several more attempts that make it worse.
Preventing it in future (the actual fix)
Since recovery is imperfect, prevention matters more. Wash cold — the single highest-return habit, and it prevents almost all accidental shrinkage. Skip the dryer or use low heat — heat in drying causes more shrinkage than washing does. Read the care label — see laundry symbols for what the icons actually mean, particularly the crossed-out tumble dryer. Air dry natural fibres and blends where you can. Turn garments inside out, which also protects prints. Applying those consistently is considerably easier than rescuing garments afterwards — and it protects colour and fit at the same time.
Quick answers
How do I unshrink clothes?
Soak in lukewarm water with hair conditioner for around 30 minutes, then gently stretch to shape and dry flat.
Does it fully restore the original size?
Usually not — expect partial recovery rather than complete restoration.
What fabrics does it work on?
Best on wool and cashmere, reasonably on cotton, partially on blends, and not on synthetics.
Can I use something other than conditioner?
Baby shampoo or wool detergent work similarly.
Should I wring it out?
No — squeeze gently and roll in a towel; wringing distorts the shape.
Can felted wool be recovered?
Essentially no — felting interlocks the fibres permanently.
How do I prevent shrinkage?
Wash cold, skip or lower the dryer heat, and follow the care label.
You're not undoing the shrinkage — you're making the fibres pliable enough to talk them partway back. Partway is usually where it ends.
The conditioner soak genuinely works, particularly on wool and cotton, and it's worth trying before writing a garment off. Use lukewarm water, soak for half an hour, stretch gently while damp, and dry flat. Just expect partial recovery rather than full restoration — and once you've got it back, wash cold and skip the dryer so you don't have to do it twice.