Trace curves off a chart image and export the underlying (x, y) data as a CSV. Everything runs locally in this page — the image is never uploaded anywhere.
Load an image to begin.
No image loaded yet. Click "Load image…" or drag a file here.
1
Crop the plot area
Drag a box around just the axes/curves, leaving out titles and outer labels. This keeps text from confusing the curve tracer.
Not set — full image will be used.
2
Calibrate X axis
Click two points on the x-axis whose values you know (e.g. two tick marks), and enter each value.
Value at point 1:
Not calibrated.
3
Calibrate Y axis
Click two points on the y-axis whose values you know, and enter each value.
Value at point 1:
Not calibrated.
4
Trace curves
If a label or legend sits on top of a curve and gets picked up, exclude that region: