Privacy
Last updated 2026-09-27
asciicharts collects no personal data. The plugin, the skill, the command line and the MCP server collect nothing at all. This website counts visits with Cloudflare Web Analytics, without cookies or personal data (see This website). There are no accounts and no advertising, and nothing is sold or shared.
The plugin and skill
The asciicharts plugin for Claude (the skill in skills/asciicharts) is instructions plus a Python script. It runs inside your Claude session. When a chart can be rendered exactly, the skill runs the bundled script, scripts/asciicharts.py, on your machine or in your session's sandbox, or the achart command if you installed it. The script reads only the chart spec or the CSV file it is given, prints the chart, and exits. It makes no network requests, writes no files and keeps nothing.
The numbers you chart go to Claude as part of your conversation, like anything else you type. How Anthropic handles your conversations is set by Anthropic's privacy policy, not by this one.
The command line and the MCP server
achart and asciicharts-mcp are programs you run yourself. They render charts from the input they receive and send nothing anywhere. An MCP server you deploy is operated by you; we run no public instance.
This website
asciicharts.online is a static site served by Cloudflare. As the host, Cloudflare processes the technical data every web request carries, such as your IP address, under Cloudflare's privacy policy.
To see how many people visit and which pages they read, the site uses Cloudflare Web Analytics. Its script, loaded from static.cloudflareinsights.com, reports page views and page load times; the reports we see are aggregate counts by page, referring site, country, browser, operating system and device type. As Cloudflare describes it, it uses no cookies or other client-side state, does not fingerprint visitors, and does not collect or use their personal data. It is the only third-party script on the site; the fonts are served from the site itself.
Your browser's local storage keeps two display preferences, the color theme and whether charts are shown in color. They never leave your browser.
Source code
Everything above can be checked in the open source code at github.com/boligolov/asciicharts.
Contact
Questions about this policy: open an issue on GitHub. If this policy changes, the new version is published on this page with a new date.