Online Plot Digitizer for Your Graphical Data
Extract Data From Graphs and Reuse It in Your Code

with our free plot digitizer tool:

extract data from scanned plots and images,
store and share datasets on SplineCloud,
access datasets directly from your code,
instantly fit curves to the extracted data.

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Benefits of SplineCloud’s Free Plot Digitizer Tool

the features that ensure you get the job done quickly with our plot digitizer free online solution

Web-based

No need to install anything on your system – use our plot digitizer online free tool with your desktop browser

Simplicity

We provide an intuitive 3-step workflow to digitize a plot: define axes -> set scale -> pick data points

Accuracy

Our plot digitizer software provides the ability to zoom into the plot to achieve better positioning of axes and data points

Data Preservation

Once digitized, your data remains in the cloud and can be reused later and shared with others

Accessibility

Digitized datasets and subsets get their IDs and can be accessed over SplineCloud API or downloaded in a 'csv' format

Instant Curve Fitting

Once data is extracted from an image, you can find the best fit for it directly on SplineCloud without the need to use side services and tools

Digitize Your Graphs

A Few Steps To Use Our Web Plot Digitizer Tool

a simple workflow with our free plot digitizer tool, explained in several steps

Step 1 - Create a Repository for Your Data

Create a repository on SplineCloud.

Upload plot images (jpg, png, bmp, webp).

Open the plot digitizer by clicking the image file.

Images may contain multiple plots — create a dataset for each.

Step 2 - Set up the Coordinate System

Click the “Define CS” button.

Place the CS origin at the plot’s origin.

Zoom in for precise positioning.

Drag bounding handles along the X and Y axes.

Set reference values to the input fields.

Select a logarithmic scale from the dropdowns if needed.

Click “Done” to confirm.

Step 3 - Pick Data Points

Double-click to add data points.

Zoom to adjust the plot scale, pan to navigate the view.

Drag points for higher positioning accuracy.

Add new subsets for multiple ranges.

For images with multiple plots, create separate datasets and restart.

Step 4 - Access Digitized Data From Code

Skip manual downloads and writing boilerplate data-loading code.

Copy Subset ID(s) from the API Link dropdown menu.

Install the Python client: pip install splinecloud-scipy.

Load data with one line: load_subset(<subset_id>).

Fit Curves To Your Plots

apply curve fitting for the extracted datasets, adjust curve shapes interactively, and reuse them in your code

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Learn More About Our Online Plot Digitizer

watch the video explaining SplineCloud's approach to plot digitizing

Turning Graphs Into Code-ready Datasets with SplineCloud

Typical Use Cases for the Online Plot Digitizer

Digitizing curves from scientific papers

Extract X–Y data points from published plots, charts, and figures when raw data is not provided.

Reconstructing engineering performance curves

Convert aerodynamic polars, thrust curves, lift/drag coefficients, engine maps, pump performance charts, and other engineering diagrams into structured datasets.

Processing scanned laboratory reports

Recover experimental data from PDFs, hand-drawn plots, or scanned measurement sheets.

Extracting material property curves

Digitize stress-strain diagrams, fatigue curves, S-N plots, creep and relaxation curves, temperature-dependent material properties, and more.

Digitizing diagrams from datasheets

Recover performance curves locked inside manufacturer datasheets and convert them into reusable digital data for further design and analysis in your code.

Comparing empirical data across multiple sources

Overlay datasets digitized from different publications or reports to analyze variations, trends, and discrepancies.

Transform Your Data Processing and Modeling Workflows

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