What actually happens to your DNA file?

When you drop your raw data file into DNAHelper it stays on your device. Here is exactly what happens — including the one deliberate exception.

Short answer

Your raw data file is never uploaded to our servers. All parsing, scoring and display happens locally in your browser. Results are saved in the browser's local storage (IndexedDB) — not with us.

Step by step: what happens in the browser

  1. You pick the file locally. The browser reads the file straight from your disk — no network request happens during the read itself.
  2. Parsing in JavaScript. The file is interpreted in memory: the format is identified (MyHeritage, 23andMe, AncestryDNA, FamilyTreeDNA or compatible), invalid rows are filtered and the genotypes build a map.
  3. Analysis against reference data. Your genotypes are compared against our trait database — still entirely in the browser. Nothing in your file leaves your device (the sole exception is opt-in DNA Chat, below).
  4. Results stored locally. Your results land in the browser's IndexedDB/localStorage. If you close the tab they stay on your device, but no server has seen them.

The only exception: DNA Chat

DNA Chat is a voluntary feature that stays off until you explicitly consent. When you use it, the following is sent:

  • your question, and
  • a selection of the genetic variants relevant to that question

…via our server to the configured AI providers (currently DeepSeek in China and NVIDIA-hosted models in the US, with processing outside the EU/EEA). Your entire raw data file is never sent — only the markers needed for context. The consent dialog appears before the first transmission and can be revoked at any time. Regular analysis works entirely without DNA Chat.

Read the full description in the privacy policy.

Compared with cloud services

Most DNA analysis services ask you to upload your raw data file to their servers — where it is often kept in their database, sometimes with broad terms for research or resale. DNAHelper flips that around: the computation moves to your device instead of your data moving to us. Technically it is not magic — modern browsers handle hundreds of thousands of genetic markers locally with ease.

What we do see (honestly)

Our server sees that a browser fetched the page — a normal access log entry with URL and timestamp, like every website has. It does not see the file, the genotypes or your results. If you create an account for a paid subscription we store your email and a technical user ID for sign-in, and Stripe handles the payment — but still no DNA data.

Want to verify it yourself?

Open your browser's developer tools (F12 → Network tab), pick your file in the app and watch the traffic: you will see no raw data uploads. Reference data for the analysis is fetched when the analysis starts — but your raw file is never sent anywhere.

Analyze my DNA file locally

Also: Local analysis vs cloud services · What is a raw DNA file? · Provider download guides · English overview