How to make a cloth mask (dated, honest about limits)

Guidance on making masks at home was written in a hurry during a supply shortage, and it was later revised. This sheet reports what two official sources said and when, gives a materials list and a method, and states what a homemade cloth mask can and cannot do. It offers no pattern download and no shopping advice, and it covers only the steps that could be read in the sources.

Read this first: dates and limits

As at 4 April 2020, the CDC page "Use of Cloth Face Coverings to Help Slow the Spread of COVID-19" described simple cloth coverings as an additional, voluntary public health measure, made at low cost from household materials. That wording belongs to the emergency period, so this sheet cites an archived copy of the page as it stood on 5 April 2020. CDC said these coverings were not surgical masks or N95 respirators, which were to be kept for healthcare workers.

WHO's interim guidance of 1 December 2020 says a non-medical mask is neither a medical device nor personal protective equipment, and that no single design, material or layering is considered optimal. It also says cloth masks have limited efficacy. A well-fitted respirator protects more, as CDC's N95 page (reviewed 12 March 2025) says even an imperfectly sealed N95 likely does better than a cloth mask. For the wider picture, see what the evidence says about masks.

What WHO says about fabric

WHO's annex says homemade masks should ideally have three layers, each with a job. The inner layer, touching the face, should be a hydrophilic (water-absorbing) material such as cotton or a cotton blend. The middle layer should be a hydrophobic (water-repelling) breathable synthetic nonwoven, and the outer layer a hydrophobic material such as polyester.

It adds that a higher thread count improves filtration, that very porous material such as gauze can have very low filtration even in several layers, and that tightly woven fabric gets harder to breathe through as layers are added. A quick check is to try breathing through the layers. WHO says coffee filters, vacuum bags and materials not meant for clothing should be avoided, and that exhalation valves are discouraged.

The CDC method below uses two layers of cotton and so differs from WHO's later three-layer ideal. Both are reported here as published.

Materials (CDC, April 2020)

• Two rectangles of tightly woven cotton, 10 by 6 inches (about 25 by 15 cm), such as quilting fabric or cotton sheets. CDC said T-shirt fabric would work in a pinch.
• Two 6-inch pieces of elastic, or hair ties, string, cloth strips or rubber bands.
• Needle and thread, scissors, and a sewing machine.

Method (CDC, April 2020)

1. Cut the two rectangles and stack them, then sew them as if they were one piece of fabric.
2. Fold the long sides over a quarter inch and hem them. Fold the double layer over half an inch along the short sides and stitch down.
3. Run a 6-inch length of 1/8-inch elastic through the wider hem on each side to make ear loops, using a large needle or bobby pin, and tie the ends tight. With string only, make the ties longer and tie the mask behind the head.
4. Pull the elastic gently so the knots tuck inside the hem, gather the sides to fit your face, and stitch the elastic in place so it does not slip.

The archived CDC page also showed a T-shirt method with scissors only and a bandana method using a coffee filter and rubber bands. Their steps appeared as pictures that could not be read as text, so they are not reproduced here. The coffee filter in the bandana version sits against WHO's later advice to avoid coffee filters.

Fit and care

CDC's 2020 criteria were a snug but comfortable fit against the side of the face, ties or ear loops, multiple layers, unrestricted breathing, and fabric that can be machine washed and dried. It said coverings should not go on children under 2, anyone with trouble breathing, or anyone unable to remove the mask without help. WHO lists a snug fit covering nose and mouth among the essential performance parameters, so fit and seal is worth reading before you rely on the result.

Wash the mask in soap or detergent, preferably in hot water, at least daily, following WHO as set out in caring for reusable masks. Put it on and take it off by the straps, as in putting on and taking off a mask.

The short version

CDC's April 2020 sewn method used two cotton rectangles and elastic, and WHO's December 2020 advice favours three layers of suitable fabric. Both were emergency-era guidance, and a cloth mask protects less than a well-fitted respirator. If you need higher protection, look at types of masks and respirators.