Claude charts turns a pasted table into an interactive, filterable visual in a single prompt. But feed it the wrong input and you get a broken output - or worse, a chart that looks right but isn't.
This page tells you exactly what works, what breaks, and where the hard limits are.
Data input formats
What Claude reads cleanly
What causes garbage output
Chart types available
What Claude can build
What Claude can't build
The two input mistakes that break everything
Mistake 1 - Skipping the header row
Mistake 2 - Not specifying the chart type
Hard limit on data volume
Claude handles up to roughly 300-500 rows reliably in a single prompt. Above that, accuracy drops - miscalculated aggregations, missed patterns, incomplete visuals.
If your dataset is larger:
→ Pre-aggregate in Attio or Sheets before pasting (summarize by week, not by day)
→ Split into separate charts by segment rather than one combined chart
→ Use the "describe my data" prompt on Subpage 2 first - Claude will tell you what's feasible before you commit









