The actual app — calibrate, trace, and export, all on one canvas.
PlotTracer pulls precise numbers out of the figures in scientific papers — stress–strain curves, rheology traces, phase diagrams — across every coordinate system your sources actually use. It records what the figure shows, and nothing it doesn't.
macOS · Windows · Linux — free, offline, no account
The actual app — calibrate, trace, and export, all on one canvas.
Mark the axes with a couple of clicks. PlotTracer learns the figure's coordinate system — linear, log, polar, or dates.
Place points with the zoom loupe, or auto-extract a whole curve by colour, fill, or blob detection. Fix anything in a click.
Send clean numbers to CSV, TSV, JSON, Excel, OpenDocument, LaTeX, MATLAB, Python or R — or straight to the clipboard, at the figure's real precision.
Scatter and fitted trends, asymmetric error bars, true histogram bins, box plots, polar plots — the same tool, on the plots you meet in practice.
Seven axis systems and a growing set of extraction targets — from ordinary XY curves to ternary phase diagrams, polar plots, spider charts, maps, and circular chart recorders. Histograms capture true bin edges, and every spoke of a spider keeps its own scale. Error bars are not a graph type here: they are captured on top of whichever series they belong to, asymmetric caps and all.
The repeated loop — calibrate, trace, correct, export — is tuned to disappear. Breadth lives in layers you can reach when you need them, never in the way when you don't.
XY, bar, polar, ternary, map and circular chart recorders — the widest coverage in the field.
Log (base-10 and natural) and date/time scales, chosen per side — exactly what the figure uses.
Trace a whole series in one pass: by colour, by connected fill, or by blob detection for scatter.
Place each cap where the figure actually draws it — asymmetric and all. The app says plainly when a cap is still mirrored rather than measured.
Records genuine bin edges and heights — the interval a bar spans, not just its centre.
Interpolation-assist traces dashed, overlapping and monochrome curves that colour tools miss — drop a few guide points, a spline fills the rest, even where a curve doubles back.
Distance, angle, area and slope — in the chart's own units or a scale you set from any length.
Polynomial, exponential, power, logarithmic, Gaussian or logistic — equation, coefficients, R² — plus arc length, area and curvature. A fit that did not settle says so, on screen and in the file. Fits export as their own block, never mixed into the record.
One calibration, any number of series — each named and colour-coded — captured side by side and exported together.
Open a paper's PDF or multi-page TIFF and capture several figures into one project.
Crop, rotate, flip, fine-deskew and remove grid lines — before or after you capture the figure.
The project bundles the original source PDF or image and records every crop and page — any number traces straight back to its figure.
One Open Project command reads WebPlotDigitizer, Engauge Digitizer and StarryDigitizer files — recognised by what is inside them, not by their extension. Anything it cannot read faithfully it refuses, and says why.
CSV, TSV, JSON, Excel, OpenDocument, LaTeX, MATLAB, Python and R — or straight to the clipboard, at the figure's real precision. Every format says up front what it cannot carry.
Full undo/redo, non-destructive edits, and a project file that round-trips exactly.
macOS, Windows and Linux. No account, no cloud, and your figures never leave your machine.
One click to a spreadsheet, a notebook, or a paper. Every value is rounded to the figure's real resolution — never padded with false precision, never collapsed to zero — with a full-precision switch when you want every digit.
No account, no cloud, no upload of your figures anywhere. Install the desktop app and start extracting.
Current release: v1.5.0 · AGPL-3.0 · source on GitHub