Ironing Temperature Table
| Fabric | Dial | °C | °F | Steam |
|---|---|---|---|---|
| Acrylic, nylon, acetate | • | 110 | 230 | off |
| Polyester | • | 110 | 230 | light, pressing cloth |
| Silk | •• | 140 | 280 | off, reverse side, dry |
| Wool | •• | 150 | 300 | light, pressing cloth |
| Viscose / rayon | •• | 150 | 300 | off, pressing cloth |
| Cotton | ••• | 210 | 410 | full |
| Linen | ••• | 230 | 445 | full, damp |
Every iron dial maps to one temperature ladder, and every fabric lives on a specific rung - get a rung wrong downward and nothing happens; get it wrong upward and the shirt carries a shiny scar forever. The table lines up each fabric with its heat, in both Celsius and Fahrenheit, plus the dial dots.
Bottom line: one dot means synthetics around 110 C (230 F), two dots means wool and silk blends around 150 C (300 F), three dots means cotton and linen at full heat 200-230 C (390-445 F). Sort the ironing pile hottest-first - linen, cotton, blends, synthetics - and you never touch the dial again mid-task.
The honest part: care labels understate on purpose - a 'cool iron' symbol protects the retailer, not the fabric. The real safety margin lives in the fiber's melt or scorch point, and blends inherit the weakest fiber in the yarn: a 60% cotton 40% polyester shirt irons at the polyester setting, never the cotton one, no matter how much it feels like a cotton shirt.
How to use
- Read the fabric - not the garment type - then find its row: heat, dial dots, and whether steam is allowed all live in the table. Unlabeled fabric? Test one inside corner at one dot and step up until wrinkles yield.
- Sort the pile high to low before you start: linen and cotton at three dots first, wool and silk at two with a pressing cloth, synthetics last on one dot once the iron has cooled - the whole session needs one dial movement.
- Scorch drill: the second you smell hot fiber, stop. Fresh shine on cotton lifts with a vinegar-dampened cloth and re-press under a pressing cloth; a melted or glazed patch on synthetics is permanent - that is the fabric itself, and no rescue reverses it.
Frequently asked questions
What temperature is the cotton setting on an iron?
Around 200 to 210 C (390-410 F), the three-dot zone where cotton wrinkles relax with full steam. Cotton scorches near 240 C (465 F), so three dots leaves margin - but stay off the max setting for anything with print, applique or elastane blended in, because those components fail well before the fiber does.
Can you iron polyester at high heat?
No - polyester melts around 250 C but starts glazing (the permanent shiny patches) far below that, near 150 C with direct contact. Iron it at one dot, 110 C (230 F), under a pressing cloth, steam off or minimal. If a polyester garment has deep creases, wash and hang-dry it instead: heat you do not apply cannot ruin the face of the fabric.
What do the dots on an iron mean?
One dot is the cool zone (about 110 C / 230 F) for acrylic, nylon and other synthetics; two dots is medium (about 150 C / 300 F) for wool, silk and polyester blends; three dots is hot (200-230 C / 390-445 F) for cotton and linen. The dots appear on both garment care labels and the iron dial - match them and you are within the manufacturer's tested window every time.
Do you iron silk with steam?
Better without: silk at the two-dot setting, flipped to the reverse side, pressed dry or with the steam off - water droplets leave spotting and texture changes on many silks. If the label says steam is fine, use it vertically (holding the iron just above, steaming rather than pressing) and keep the iron moving; dwell time is what damages protein fibers.