Extract data from chart images to CSV

DataFromChart and PlotDigitizer.com are the two main browser-based chart digitizers in 2026. Both run in a tab, both do color-based auto-extraction, both finish a chart in under five minutes — but they diverge on output, pricing, and AI features. Pick DataFromChart for XLSX with chart embedded and AI calibration on the free tier; pick PlotDigitizer.com if muscle memory beats the feature delta.

At a glance

	DataFromChart	PlotDigitizer.com
Pricing	Free for individual extraction	Freemium (paywall on XLSX + batch)
Install	None	None
Axis types	Linear, log, date	Linear, log
Vision-LLM point extraction	Yes	No
Color auto-extraction	Yes (with live tolerance preview)	Yes
CSV / TSV	Yes	Yes
XLSX with chart embedded	Yes	Paid tier only, no chart embed
JSON	Yes	Limited
Project save / resume	Yes	Yes
Account required	No (to try)	Yes (free account)

What each one is best at

DataFromChart wins on AI and export. The “detect axes and extract” flow runs a vision model that picks endpoints, so on a familiar bar or line chart you skip most calibration. XLSX embeds the chart image plus axis labels with units. Color tolerance is a live overlay rather than a number you guess.

PlotDigitizer.com wins on familiarity. Competent UI, stable extraction loop, easy to find from a generic search. If you’ve trained your eye on its tolerance dial and your CSV pipeline is wired up downstream, switching costs more than it saves.

Workflow comparison

Calibration. PlotDigitizer.com is manual: click two x endpoints, enter values, repeat for y. DataFromChart offers the same plus AI that reads axis labels and proposes endpoints — accept, nudge, or override.

Auto-extraction. Both do color segmentation. DataFromChart’s tolerance preview updates as you drag; PlotDigitizer.com’s is a numeric value with no preview — fine once you know your number, slower the first time.

Series handling. Both support multi-series by re-running per color. DataFromChart’s picker is in the points panel; PlotDigitizer.com keeps it in a sidebar. Neither auto-segments multi-color in one pass.

Export. PlotDigitizer.com: CSV free; XLSX, batch, project paid. DataFromChart: CSV, TSV, XLSX (chart embedded), JSON, all free.

When to pick DataFromChart

Excel with source chart embedded — for a stakeholder, co-reviewer, or your future self.
No paid subscription for a few-times-a-month tool.
Chart type AI calibration handles well (most published bars, lines, scatters); skip endpoint-clicking.
Live tolerance preview when tuning color extraction.

When to pick PlotDigitizer.com

Years of muscle memory worth the friction of switching.
Workflow built around its project files.
Linear-only charts, CSV is your one output.

Pricing

PlotDigitizer.com is freemium: core extraction free; XLSX, batch, advanced features paid. Per-month per-user.

DataFromChart is free for individual extraction, XLSX and all single-chart features included. Team and bulk on the pricing page. For “digitize one chart into a spreadsheet,” DataFromChart’s free tier covers more ground.

Accuracy

Same math — linear interpolation between two calibration points per axis — both land within ~0.5% on a clean image. Image and calibration set the ceiling.

Edge cases:

Tiny source images (under ~800 px wide): DataFromChart’s sub-pixel calibration handle helps; PlotDigitizer.com’s snap-to-pixel can introduce 1–2% drift.
Dense scatter plots: comparable.
Log axes: comparable; both handle log10 cleanly.

Migrating between them

Both export CSV: extract, export, re-import. Project files don’t round-trip — not unique to this pair, no two digitizers share a project format.

Run the same chart through both. Open DataFromChart’s extractor and put a chart through it; then the same on PlotDigitizer.com. Two tabs, ten minutes, decisive answer.