Deltaline draws every chart locally, inside Excel. Your workbook data is never uploaded anywhere. This page is the plain-words version of what goes over the network and what is stored where.
The formal document is the Deltaline Privacy Policy. For IT and security reviews there is also the Deltaline security and architecture page.
Your workbook data never leaves Excel #
Reading the cells a chart is linked to, following their changes, drawing the chart and exporting a file all happen inside Excel on your device. We do not receive, store or have any access to your workbook contents. Deltaline writes to your cells in two cases only: when you start from a sample, it writes a small sample table into empty cells; when you type a comment on a chart, it writes the comment into the Comments column of that chart’s data (or a new Comments column next to it). It never changes the cells that hold your numbers.
What goes over the network #
- Loading the add-in. Every chart, and the chart editor, loads its code from addins.pythonandvba.com and Microsoft’s office.js, like any add-in. These requests carry no workbook data.
- Viewers make no license call. Opening, viewing or recalculating a workbook with Deltaline charts never contacts the license server.
- Authors make one license check per author action: opening the editor, clicking Apply, or adding a key. It sends your license key, an anonymous installation identifier (a random value created on your device, not derived from your hardware) and the add-in version. Enter no key and the request is never made.
- Nothing else. No analytics, no advertising, no tracking, no cookies and no automatic error reporting.
A record of the last successful check stays on your device so licensed features keep working for a 7 day offline grace period when the license server cannot be reached.
What is stored in your workbook #
Each chart’s settings (chart type, which cells it is linked to, options, titles, and a small copy of the most recently drawn data) and a snapshot image of the chart are stored inside the workbook file by Office. That is what keeps the chart working after save and reopen. It travels with the file like the cells themselves, and it never contains a license key.
What stays on your device #
Your license key, the installation identifier, the date of your first use (which anchors the free trial), your presets, brand colors, your dashboard collection and a picture of each chart’s last drawing (so a chart shows at once when Excel reloads it) live in the add-in’s local storage on your device.
What you create carries your data #
- Exported files (PNG images, copied images, interactive HTML charts, dashboard pages) are generated on your device and go where you save or paste them. They include the charted values.
- Share links carry the chart and its values inside the link itself. Nothing is uploaded, but anyone with the link can see the chart.
- A shared workbook contains its data and each chart’s settings, as described above.
Each of these is created only when you ask for it, and none of them travel through us.