Chart to Data
Read approximate values from a clear two-dimensional bar or line chart after confirming its axes.
Fill in the fields, then submit when you are ready.
Result
Your result will appear here after you submit and complete verification.
How to use Chart to Data
- Choose one clear PNG, JPEG or WebP image of a two-dimensional single-series bar or line chart. Prefer the original dataset if it is available.
- Confirm Chart type, both axis labels and the linear vertical minimum and maximum from the image. The maximum must be greater than the minimum; add Chart context only when it helps identify the supplied chart.
- Select Read chart values and complete browser verification when prompted. Compare every returned label and approximate value with the image; unsupported charts should return a reason without a data CSV.
- Use Review and edit locally to correct the title, point labels, horizontal values or vertical readings. The confirmed axes stay fixed, and edits remain in this page rather than changing the original server result.
- Use Download edited CSV for the reviewed browser table, or Download CSV for the original accepted reading. Keep the approximation warning with either file; corrected axes require a new request.
Example: Chart to Data
Read three labeled bars from a small chart.
Options
- Confirmed axes
- Read the labels and bounds from the chart yourself. A mistaken scale can make every extracted value misleading.
- Local review table
- Change labels or values in the browser before downloading edited CSV. Values must remain finite and inside the confirmed vertical range.
Supported inputs and limits
- Use one PNG, JPEG or WebP image up to 5 MiB, 12 megapixels and 8,192 pixels on either side.
- Supported readings contain 1 to 30 points from a clear, two-dimensional single-series bar or line chart with a linear vertical axis.
- Pie, stacked, logarithmic, three-dimensional and multiple-series charts are outside scope.
- Axis labels allow 100 characters each and Chart context 500.
- Confirmed vertical bounds must be finite within -1,000,000,000 to 1,000,000,000, with maximum greater than minimum.
More details
Returned or locally edited vertical values stay inside those bounds; point labels must be unique.
All values remain approximate image readings, even if many decimal places are returned.
Local edits do not update the original server download and are lost when the page is reset or left.
The tool does not recover the original dataset or verify the chart’s reporting.
Where your input is processed
Your input is uploaded to this site and sent to a configured AI provider. If a provider fails, the request may be sent to the next eligible provider. Check its result before use. Private inputs and results expire within one hour and are excluded from site backups; temporary files are removed by scheduled cleanup. Provider retention rules may differ. Avoid submitting passwords or highly sensitive information.
Keep the chart context with the numbers
Check whether the vertical axis starts at zero, whether intervals are equal and what each unit means. Compare the number of points and their labels with the chart, then review the highest and lowest values before the rest. The original Download CSV includes an Approximate column set to yes, along with confirmed axes. Download edited CSV retains the title and axes but has no separate approximation column, so keep that warning with the edited file when sharing or reusing it.
Questions about Chart to Data
Are the values exact?
No. Image resolution, line thickness and axis interpretation affect readings. Prefer the original dataset whenever it is available.
What happens to an unsupported chart?
The result should explain why it cannot provide a supported reading. It does not produce a data CSV for a refused chart.
Can I change the vertical scale after extraction?
Start a new request with corrected axes. The local review table uses the axes you confirmed for that result so edits cannot silently change its scale.