Chart Patterns
Rounding Bottom / Saucer
A slow U-shaped reversal, the decline decelerates into a flat base and then gradually reaccelerates back up, no sharp V anywhere in the sequence.
Fit the curve, read the rate
The gold dashed line is a real parabola anchored to the chart's actual lowest bar. Drag the curvature slider until it hugs the real swing lows as closely as possible. R-squared tells you exactly how good the fit is, not a guess. Some setups below are not genuine rounding bottoms at all, they are sharp V-shaped drops with the same total depth, and no amount of curvature dragging will fit a parabola to a V.
Drag the slider to begin fitting.
How it works
- The vertex is found automatically, not guessed. The tool scans the base for its actual lowest low and anchors the parabola there. You only control one number, the curvature, which sets how sharply the bowl opens up from that fixed point.
- R-squared is computed against the real lows, bar by bar. For every bar in the base, the tool compares your fitted curve's price to the bar's actual low and sums the squared error, then converts that into the familiar 0-to-1 goodness-of-fit score. A fit of 0.85 or higher unlocks the handle and breakout.
- The three rate boxes are fixed, they do not move when you drag the slider. They report the real average bar-to-bar change in the lows across the first third, the middle half, and the last third of the base. A genuine rounding bottom shows a steep negative rate up front, a rate close to zero in the middle, and a steep positive rate at the end, proving the deceleration and reacceleration are real and not just how the chart happens to look.
- A V-shaped drop has the same total depth but a flat rate profile. Its decline and recovery legs are straight lines, so the middle-third rate stays almost as steep as the edges instead of flattening out, and no curvature setting fits a parabola to it above roughly 0.6 R-squared.
Where this breaks
A rounding bottom is obvious once it is finished and nearly impossible to call while it is still forming
This tool lets you fit a curve against a base that already has all 22 bars printed, which makes the smooth U-shape easy to see and easy to score. Live, a trader watching bar 10 of a potential rounding bottom has no idea whether bar 15 will keep flattening out or roll straight back into a fresh leg down, and the R-squared number this tool shows you cannot exist yet because the second half of the curve has not happened. The pattern's entire identity, the gradual deceleration and reacceleration, can only be confirmed in hindsight, and by the time enough bars have printed to confirm it with any confidence, a meaningful chunk of the eventual move off the bottom has often already happened without you in it.