Building a star on Earth means winning three fights at once — hot enough, dense enough, held together long enough. The Lawson criterion is the scoreboard.
Fusion (Lawson Criterion)Live
the recipe for a star on Earth
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To get more fusion energy out than you put in, a plasma must be hot enough, dense enough, and confined long enough — captured together in the triple product n·τ·T. The Lawson criterion sets the threshold for ignition, where the fusion self-heats. Crossing it, at over 100 million degrees, is the decades-long goal of tokamaks and laser fusion.
Reading this result: Sub-ignition at 50% — the plasma leaks heat faster than fusion replaces it, so raise density, confinement time, or temperature to close the gap.
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How it works
For fusion to produce net energy, a plasma must satisfy the Lawson criterion, captured in the triple product of density, confinement time, and temperature (n·τ·T). Crossing the ignition threshold — where fusion self-heating sustains the reaction — at temperatures over 100 million degrees is the central goal of tokamaks and inertial-confinement laser fusion.
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Is this fusion Lawson criterion triple product tool really free?▾
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The solver uses established numerical methods, but results are for research and educational purposes and should be validated against experiment or professional review before you rely on them.