Forging Temperature Chart
Quick answer
Pick a steel grade and this chart shows its forging range in °F and °C, the glow colour to look for, and the temperature where it starts to burn. Most carbon steels forge bright orange to yellow around 1,500-2,100°F; mild steel takes a wider, hotter range. Judge colour in dim light.
1084 forging heat
Glow colour: Bright orange to yellow. Stop before 2,200°F - past that, 1084 starts to burn and spark. Typical use: Simple high-carbon knife steel - forgiving heat range for beginners.
Forge by colour, in low light
Steel tells you its temperature by how it glows. Judge the colour in dim light - bright shop lighting makes hot steel look cooler than it is, so you overheat it. Work down from the top of the range; when the colour fades past the low end, stop hammering and reheat rather than forcing cold metal.
Every grade has a different safe window. Simple steels like 1084 and mild steel are forgiving; tighter grades like O1 punish overheating. See the full forging temperature table for every steel at once.
Frequently asked questions
What temperature do you forge steel at?
Most carbon and tool steels forge in a roughly 1500-2100°F window, glowing bright orange to yellow. Mild steel tolerates a wider range up to about 2300°F. Always work below the grade's overheat point - shown above for the steel you picked - because past it the steel burns and is ruined.
How do I know if I overheated the steel?
Overheated steel throws bright sparks (burning carbon), looks wet or shiny at the surface, and may crumble or crack under the hammer. If you see sparks coming off the piece in the forge, it is too hot - pull it and let it cool, and turn the forge down.
Why forge in dim light?
Colour is your thermometer, and daylight or bright shop lights wash out the glow so steel looks cooler than it really is. Smiths dim the lights near the forge so they can read colour accurately and avoid overheating. It is the simplest way to hit the right temperature without instruments.
Is this the same as tempering colours?
No. This chart shows forging (red-hot) temperatures around 1500-2300°F. Tempering colours (straw, bronze, blue) appear on polished, already-hardened steel at far lower temperatures, roughly 400-600°F. Do not confuse the two - they are different jobs at very different heats.