How to Prevent Clothes from Shrinking in the Dryer

We've all experienced that sinking feeling: pulling a favourite jumper from the dryer only to find it's now several sizes too small. Shrinkage is one of the most common and frustrating laundry mishaps, but it's largely preventable once you understand what causes it and how to adjust your drying habits.

This guide explains the science behind fabric shrinkage and provides practical strategies to keep your clothes looking and fitting their best, load after load.

Understanding Why Clothes Shrink

Shrinkage isn't just about heat, though heat is the primary trigger. Several factors work together to cause clothes to reduce in size:

Relaxation Shrinkage

During manufacturing, fabrics are stretched and held under tension. When exposed to water and heat, fibres relax and contract back toward their natural state. This type of shrinkage typically occurs during the first few washes and dries.

Felting Shrinkage

Wool and animal fibres have scales on their surface. Heat, moisture, and agitation cause these scales to interlock permanently, dramatically reducing size and creating a dense, matted texture. This is irreversible once it occurs.

Consolidation Shrinkage

Cotton and plant fibres can shrink when heat causes their molecular structure to tighten. Unlike relaxation shrinkage, this can continue to occur with repeated high-heat drying.

Prevention Strategy 1: Check Care Labels

This seems obvious, but it's the most important step. Care labels exist because manufacturers understand their fabrics' limitations. The tumble dry symbols to look for:

• Square with circle inside: Tumble drying permitted
• One dot in circle: Low heat only
• Two dots: Medium heat acceptable
• Three dots: High heat okay
• X through symbol: Do not tumble dry
• Empty circle: No heat (air dry only)

When in doubt, treat an item as if it required the gentlest treatment. A shirt that takes slightly longer to dry is better than a shirt that no longer fits.

Prevention Strategy 2: Use Lower Heat Settings

Heat is the primary driver of shrinkage. Reducing temperature is the single most effective prevention measure. Most dryers offer multiple heat settings:

• High heat (70-75°C): Reserve for towels, cotton sheets, and items explicitly labelled for high heat
• Medium heat (55-60°C): Suitable for most everyday cotton items
• Low heat (40-50°C): Best for synthetic blends and items prone to shrinkage
• Air dry/No heat: Safest option for delicates and shrink-prone items

Lower heat means longer drying times, but modern sensor dryers compensate automatically. The energy difference is minimal, and your clothes last significantly longer.

Prevention Strategy 3: Don't Overdry

Extended exposure to heat, even at lower temperatures, increases shrinkage risk. Overdrying also damages fibres, fades colours, and sets wrinkles.

Use sensor drying programs whenever possible. These detect when clothes reach the target moisture level and stop the cycle automatically. If using timed drying, check clothes a few minutes before the cycle ends and remove any that are already dry.

Many dryers offer settings like "cupboard dry" (completely dry) or "iron dry" (slightly damp for easier ironing). For shrink-prone items, stopping at slightly damp and air drying the rest of the way is safer.

Prevention Strategy 4: Remove Clothes Promptly

Leaving clothes in a hot dryer continues to expose them to heat, even after the cycle ends. Residual heat in the drum and clothes themselves can cause additional shrinkage and definitely sets wrinkles.

If you can't unload immediately, use your dryer's anti-crease feature if it has one. This periodically tumbles clothes without heat to prevent them sitting compacted and warm.

Prevention Strategy 5: Sort by Fabric Type

Mixing heavy items with delicates forces a compromise on heat and time that doesn't suit either. When you dry a load of jeans with cotton t-shirts, either the jeans stay damp or the t-shirts get overdried.

Sort laundry into groups with similar heat tolerance:

• Robust cottons: Towels, sheets, underwear, socks
• Everyday cottons: T-shirts, casual shirts, casual pants
• Delicates: Synthetics, stretchy items, dress clothes
• Special care: Wool, silk, items with embellishments

Prevention Strategy 6: Use Mesh Laundry Bags

Mesh laundry bags reduce mechanical stress on delicate items during tumbling. While they don't prevent heat-related shrinkage, they protect against stretching, tangling, and wear that can compound damage from heat.

Use bags for:

• Bras and underwear
• Delicate knits
• Items with straps, hooks, or ties
• Small items that might get lost or tangled

Prevention Strategy 7: Pre-Shrink New Items

Some shrinkage is inevitable for natural fibres. Rather than risk ruining a garment at an inopportune time, intentionally shrink new items under controlled conditions.

Wash new cotton and linen items in warm water and dry on medium heat before wearing. This releases relaxation shrinkage while you can still exchange if the size changes significantly. After this initial treatment, use gentler settings to prevent further shrinkage.

Special Fabric Considerations

Wool

Wool requires extreme care. Never tumble dry wool on any heat setting unless the care label explicitly permits it. Heat and agitation cause irreversible felting. Use the air-dry setting only, or better yet, lay flat to dry outside the dryer.

Cotton

Most cotton can be tumble dried, but high heat causes cumulative shrinkage over time. Use medium heat for everyday cotton and low heat for fitted items where sizing matters. Pre-shrunk cotton is more forgiving but not immune.

Synthetic Blends

Polyester, nylon, and similar synthetics generally resist shrinkage but can be damaged by high heat in other ways (melting, pilling, permanent creasing). Use low or medium heat for synthetics and blends.

Denim

Jeans shrink, especially raw or unwashed denim. If you want to maintain exact fit, dry on low heat and remove while slightly damp. Many people intentionally shrink jeans for a closer fit, but be aware this is hard to reverse.

Signs Your Dryer Settings Need Adjustment

Watch for these indicators that you're drying too hot:

• Clothes feel stiff or crispy rather than soft
• Colours are fading faster than expected
• Elastic in underwear and sportswear is deteriorating
• T-shirts are becoming shorter or tighter
• Print graphics are cracking or peeling

If you notice these signs, reduce your heat settings and consider our tips for energy-efficient drying, which naturally involve gentler treatment.

Summary: Your Anti-Shrinkage Checklist

• Always check care labels before drying
• Use the lowest heat setting that gets the job done
• Don't overdry - use sensor programs when available
• Remove clothes promptly when the cycle ends
• Sort loads by fabric type and heat tolerance
• Pre-shrink new natural fibre items before wearing
• Consider a heat pump dryer for naturally gentler drying

With these strategies, you can enjoy the convenience of your dryer while keeping your wardrobe in top condition for years to come.