Core terms
R-multiple
A trade's result divided by its planned risk. 1R is the amount a trader planned to lose if the stop was hit; a result of +2R made twice that amount.
For a long trade, 1R per share is entry minus stop. If a trade enters at $2.89 with a stop at $2.81, 1R is $0.08 per share; at 625 shares, 1R is $50. Exiting at $3.05 with $0.005 per share in fees is ($3.05 − $2.89 − $0.005) ÷ $0.08 = +1.94R after costs (Illustrative).
R makes trades of different sizes comparable and makes cost drag visible. It also shows when realized losses exceed plan: a stop that fills two cents below its price turns a planned −1R into about −1.31R in the same example.
What traders should verify
Record planned risk in dollars before entry, then compute gross and net R for every trade. Watch for losses beyond −1R; they point to slippage, halts or stops that were moved.
Do not conflate
Trader usage; there is no official definition. R depends on where the stop was planned, so moving a stop changes what 1R means. Comparing R across traders is only meaningful if they define it the same way.
Primary source
Trader usage: there is no official definition, and platforms and tools may calculate it differently.