Copper Pour Heatsink Calculator
Temperature rise of a copper pour used as a heatsink — flat-plate convection model with the pour size needed for your power.
First-order estimate: it assumes the copper spreads heat evenly (true within ~25–50 mm of the source for 1–2 oz copper) and still air. Forced airflow can triple h; a small device heating one corner of a big pour will run hotter than this predicts. For regulator/MOSFET tabs, also check the junction-to-tab θ from the datasheet — the silicon adds its own rise on top of this.
Copper Pour Heatsink Calculator computes the temperature rise of a copper pour used as a free heatsink — free, instant and private in your browser. Designers cooling regulators, MOSFETs and LED drivers without a bolt-on heatsink use it to skip the datasheet algebra: type your numbers, read the answer with the substituted formula shown step by step, and share an exact permalink of the calculation.
About Copper Pour Heatsink Calculator
Copper Pour Heatsink Calculator computes the temperature rise of a copper pour used as a free heatsink using the standard engineering relation: Rθ = 1/(h·A) with still-air h ≈ 10 W/(m²·K), then ΔT = P·Rθ. Worked live: a 25 × 25 mm single-sided pour is roughly 160 °C/W — 1 W heats it ~160 °C above ambient, so you need more copper. The result recalculates on every keystroke, the worked-example panel shows your numbers substituted into the formula, and the Copy permalink button encodes the inputs in the URL so a colleague opens exactly your calculation. Everything runs client-side — nothing you type leaves your device.
How to use Copper Pour Heatsink Calculator
- 1Enter your values — the tool starts with realistic defaults for this exact use case, so the worked example is meaningful immediately.
- 2Read the live result and the worked-example panel, which substitutes your numbers into the formula step by step.
- 3Adjust any input to compare scenarios, then use Copy result or Copy permalink to share the calculation.
Why use Copper Pour Heatsink Calculator?
- ✓Implements the real formula — Rθ = 1/(h·A) with still-air h ≈ 10 W/(m²·K), then ΔT = P·Rθ — with the substitution shown, not a black box
- ✓Built for designers cooling regulators, MOSFETs and LED drivers without a bolt-on heatsink
- ✓Copy result and permalink buttons — share the exact calculation in a README, forum answer or design review
- ✓100% free, no sign-up, runs entirely in your browser (works offline once loaded)
Frequently asked questions
How do you calculate copper pour heatsink?+
The temperature rise of a copper pour used as a free heatsink follows Rθ = 1/(h·A) with still-air h ≈ 10 W/(m²·K), then ΔT = P·Rθ. For example, a 25 × 25 mm single-sided pour is roughly 160 °C/W — 1 W heats it ~160 °C above ambient, so you need more copper. The calculator applies the same relation and shows the substituted arithmetic so you can verify every step.
How big a copper pour do I need for 1 W?+
For a 40 °C rise in still air you need about 25 cm² of exposed copper — a 50 × 50 mm pour single-sided, or ~35 × 35 mm if both faces see air. Forced airflow can cut that by two-thirds.
Does pouring copper on both sides really help?+
Yes, nearly double, IF the bottom face also sees air and you stitch the two pours with a via grid under the hot part. A pour facing an enclosure wall a millimetre away helps far less — count only faces with real airflow.
Is the Copper Pour Heatsink Calculator free and private?+
Yes — completely free with no sign-up or usage limits, and it runs entirely in your browser: the values you enter are never uploaded or stored on a server.
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