What we keep, and what we don't.

The short version

We collect the questions you ask and basic usage counts, so the tool can answer better and stay within its limits. We do not use advertising or analytics trackers, and we do not sell your data. On the free tier, the boards you save are public — that is the trade for free use, and it is stated again below where it matters. Everything else is detail.

The catalog website

The pages you are reading now are static and served by our hosting provider. Like any web host, it records standard access logs — your IP address, the page requested, and your browser's user-agent string — for security and to keep the service running. There are no advertising cookies, no third-party analytics, and no cross-site trackers on this site. Your browser stores one thing locally: your light/dark theme preference. That never leaves your device.

The app — when you ask a question

When you use the tool to resolve a question into a chart, we handle:

• Your questions. The text you type is stored so the resolver can learn from real demand — which indicators people ask for, and which ones have no open source yet. Write questions about data, not about yourself.
• Usage records. Which datasets a request fetched, and counts of requests, so we can apply tier limits and measure load. A repeated question that we have already answered is served from cache and costs nothing.
• Your network address, on the free tier only. With no account we identify a free user by their IP address to apply the daily limit. It is used to rate-limit, not to build a profile, and IPv6 addresses are grouped to a network block rather than an individual device.
• Your account, on paid tiers. An API key and the credit balance attached to it.

Saved boards — free boards are public

A board is a set of saved questions. On the free tier, your boards are public. They appear in the Explore feed, and anyone can open and copy them. This is deliberate — public boards are how the free tier stays free and how people find ideas. When a board is shown to others, the author is an anonymised handle derived from a one-way hash; your API key, email and IP address are never shown. Paid boards are private by default, and paid users can make any board public or private per board. Do not put anything you consider private into a free-tier board.

Who else touches the data

• AI providers, for some questions. When our own resolver cannot parse a question — for example one written in another language, or phrased unusually — the text of that question may be sent to an AI service (OpenAI or Anthropic) to rewrite it into a clean query. We send only the question text, never your identity, and only when our own engine has already failed. Plain, working English questions are handled entirely by us and are never sent anywhere.
• Payment providers. Card payments are handled by our payments provider acting as merchant of record; we never see or store your card number. Payments made by stablecoin record only the public on-chain transaction reference. We do not store financial credentials.
• Our hosting and infrastructure. Providers who run the servers and database, bound to process data only to operate the service.

What we do not do

No advertising trackers. No selling or renting of personal data. No third-party marketing or analytics cookies, and so no cookie-consent wall — because there is nothing to consent to beyond the functional storage described above. The statistical values in a chart come from public bodies (see Attribution) and are not personal data.

How long we keep things

Usage and question logs are pruned on a rolling basis (about 90 days). Saved boards and account records are kept until you delete them. Records needed for billing and tax are kept as long as the law requires.

Your choices

• Delete any board, or any card in it, at any time in the app.
• On a paid tier, set any board public or private.
• Ask us to delete the data associated with your account or free-tier bucket by writing to the contact below.

Children

StackData is a tool for working with public statistics and is not directed at children.

Who is responsible, changes, and contact

StackData is operated by an individual based in California, United States — the person responsible for the data described here. There is no company behind it. If this policy changes materially, the update will be posted here with a new date. Questions or requests: privacy@stackdata.io.

Last updated: August 2026.