Ironing Symbols: What the Dots Mean and Which Temperature to Use

On ironing symbols, the number of dots shows the maximum allowed temperature: one dot is the lowest, three dots the highest. A crossed-out iron means the garment must not be ironed. The simplest rule is to match the number of dots on the care label with the dots on your iron's temperature dial.

What do the dots on the iron symbol mean?

Ironing symbols are defined by the international standard ISO 3758. Under its latest edition from 2023:

• One dot – iron at up to 120 °C, without steam. Usually found on delicate synthetics: polyamide (nylon) and acetate.
• Two dots – iron at up to 160 °C, steam allowed. Usually found on wool, silk, polyester and viscose.
• Three dots – iron at up to 210 °C, steam allowed. Usually found on cotton and linen.
• Crossed-out iron – do not iron: the iron would damage the fabric permanently.

Older labels and many guides give slightly lower values – 110, 150 and 200 °C, which applied until the standard was updated in 2023. In practice the 10 °C difference does not matter, because irons show temperature with the same dots rather than in degrees.

How do you set the iron temperature by the symbol?

Most irons have the same dots on the temperature dial: •, •• and •••. Set as many dots as the label shows. If your iron lists fabric names instead of dots, choose the setting that matches the fabric composition on the label.

Start with the lowest temperature: one-dot garments first, then two-dot ones, and cotton and linen last. An iron heats up quickly but cools down slowly, so synthetics ironed straight after cotton are easy to damage.

Ironing temperature by fabric

• Linen – three dots. Iron while slightly damp, with steam. Iron dark linen inside out to avoid shine.
• Cotton – three dots. With steam; if the fabric has dried out completely, dampen it first.
• Wool – two dots. With steam, through a damp cotton cloth, without pressing hard.
• Silk – two dots, or lower if the label says so. Inside out, without pressing hard. Do not spray water directly onto silk – it can leave marks.
• Polyester and viscose – two dots. Iron viscose inside out so it does not turn shiny.
• Polyamide (nylon) and acetate – one dot, no steam.
• Blended fabrics – choose the temperature for the most delicate fibre in the blend.

When should you iron with steam, and when not?

Two and three dots allow steam, one dot does not. According to the standard, steam can cause irreversible damage to one-dot fabrics. Some labels show crossed-out steam lines under the iron – this also means ironing without steam.

Use distilled water in your steam iron. It contains no limescale, so the steam vents do not clog and no brown marks are left on light-coloured clothes. Alchemy by RM scented distilled water also carries a subtle fragrance into the fabric with the steam. Read more in how distilled water makes ironing easier.

What should you do if the iron is crossed out?

Do not iron the garment. There are gentler ways to remove wrinkles:

• Bathroom steam. If steam is not prohibited on the label, hang the garment in the bathroom while you take a hot shower: the moisture relaxes the fibres.
• Wrinkle release spray. A few sprays and a gentle stretch of the fabric by hand are enough. Test the scented wrinkle release spray on a hidden area before first use.

More methods in how to get rid of wrinkles without an iron.

Frequently asked questions

What if there is no label, or it has faded?

Start at the lowest temperature and test on a hidden area, such as the inside of a seam. If the wrinkles do not come out, raise the temperature one setting at a time.

Can I iron at a higher temperature than the symbol shows?

No. The dots show the maximum allowed temperature; a lower one is always fine.

Why does a garment look shiny after ironing?

Usually because the temperature was too high or the iron was pressed too hard. Iron such fabrics inside out or through a cotton cloth.

You will find scented distilled water for your iron in our distilled water for irons collection.