Privacy Policy — Goal Seek for Google Sheets

Effective date: 16 October 2026 · Last updated: 16 October 2026

Summary: Goal Seek runs entirely inside Google Sheets, in the one spreadsheet you open it in. It has no external servers, makes no network requests, uses no analytics and no cookies. No spreadsheet data — personal or otherwise — is ever transmitted to us or to any third party. All data stays inside your Google account, protected by Google's encryption in transit and at rest (see section 6).

1. Who we are

Goal Seek ("the add-on") is operated by Fabian Hönes (contact: kontakt@arbeitstyp.de). For the data the add-on processes inside your spreadsheet we are neither a data controller nor a data processor — that data is processed entirely within your Google account and never reaches us (sections 2–6). We act as a data controller only for support correspondence you choose to send us directly (section 10).

2. Google user data the add-on accesses

The add-on requests exactly two OAuth scopes — the minimum required for its single function:

…/auth/spreadsheets.currentonly — read and modify only the spreadsheet this add-on is used in. The add-on cannot see any of your other files.
…/auth/script.container.ui — show its sidebar inside Google Sheets. Google classifies this scope as sensitive; it displays the add-on's user interface and grants no access to your data by itself.

Through these scopes the add-on accesses, in the spreadsheet you use it in: the value and formula of the target cell and the variable cell you select, the recalculated values during the search, the sidebar form inputs you type, and the address of the cell currently selected in the sheet and whether it holds a formula (so that clicking a cell can fill a field). To suggest suitable variable cells, it also reads the formulas and values of the cells your target formula refers to, directly or through other formulas (at most 40 cells), and the neighbouring cells to the left of and above each suggested cell, whose text it shows as a label. It also reads the spreadsheet's locale and time zone and your language setting, so that numbers and dates are read and shown correctly. It accesses nothing else — not your other spreadsheets, not your Drive, not your contacts, not your email, not your account profile.

3. How that data is used

When you run a goal seek, the add-on reads the value of the target cell and of the variable cell you selected, writes trial values into that one variable cell, and reads the recalculated target value until a solution is found. Before the first write it saves the original content of the variable cell into the spreadsheet's own document properties, so it can always be restored — after a cancel, an error, or an interrupted run. While you fill in the form, it shows the current values of the cells you chose and suggests variable cells as described in section 2; these reads only produce hints in the sidebar and are not stored. It also remembers your last form inputs per spreadsheet, so the sidebar can prefill them next time, and counts your successful runs, so that after a few of them it can ask whether you would like to rate the add-on. That is the only use of the data — providing the goal-seek feature you invoked. There is no secondary use of any kind.

4. Where data is stored, and for how long (retention)

All processing happens inside Google's infrastructure, executed by Google Apps Script under your own Google account. Nothing is copied to any system outside your Google account. We — the developer — operate no servers and no databases, and we never see, receive, store or retain any of your spreadsheet data.

The add-on persists only the following, all in Google Apps Script's storage for your account:

the saved original content of the variable cell, in the spreadsheet's own document properties, until the run is over and the cell either keeps the new value or has its original content back;
while a run is active, a short marker in the same document properties that stops two people from running Goal Seek on one spreadsheet at the same time; it is removed when the run ends. The marker and the saved original content are filed under a temporary, anonymous user key provided by Google, so that several people can use the add-on in one spreadsheet;
your last sidebar inputs (cell references, target value and advanced options), stored per spreadsheet ID for up to the 20 spreadsheets you used most recently, in the add-on's user properties. These belong to your Google account and only the add-on can read them, while you use it;
in the same user properties, the number of your successful runs and whether you have answered the rating request.

Document properties live inside the spreadsheet and are deleted together with it. The user properties contain no cell values other than the references and numbers you typed into the form; older entries are replaced automatically. Because no data ever reaches us, our own retention period for Google user data is zero.

5. Sharing of Google user data

We do not share, transfer, sell or disclose Google user data to anyone — no third parties, no service providers, no advertisers, no data brokers. Technically we could not even do so, because the data never leaves your Google account. The add-on makes no network requests to any external system (no egress) and uses no cookies, analytics, tracking or advertising of any kind.

6. Data protection mechanisms

We protect the data the add-on touches with the following mechanisms:

Encryption in transit. All communication between your browser, the add-on's sidebar and Google's servers uses HTTPS/TLS, enforced by Google's infrastructure. The add-on itself opens no other connections.
Encryption at rest. Everything the add-on reads or writes (cell values, document and user properties) is stored by Google and is encrypted at rest by Google as described in Google's default encryption documentation.
Data minimization & least privilege. The add-on requests the narrowest available scopes (section 2): it can only touch the spreadsheet it runs in, and only while you use it. It reads only the cells involved in the goal-seek you configure and, for the suggestions, the cells your target formula depends on.
No external attack surface. With no servers, no database and no egress, there is no system of ours that could be breached to expose your data. Sandboxing and isolation of the Apps Script runtime are provided and maintained by Google.
Access control on the developer side. The developer account that publishes the add-on is protected by strong authentication (two-factor authentication). No mechanism exists by which the developer can read user spreadsheets through the add-on.
Change control. The add-on ships as reviewed, versioned releases through the Google Workspace Marketplace. Any future change to the requested scopes would trigger a new Google review and a new consent screen — the add-on's access cannot silently expand.
Incident response. In the unlikely event of a security incident affecting user data, we will notify affected users and the relevant authorities without undue delay, in accordance with Art. 33/34 GDPR.

7. No AI/ML training (Workspace API disclosure)

We do not retain or use any data obtained through Google Workspace APIs to develop, improve or train generalized (non-personalized) artificial intelligence or machine-learning models. The add-on contains no AI components; it is a deterministic numerical solver.

8. Limited Use

Goal Seek's use of information received from Google APIs adheres to the Google API Services User Data Policy, including the Limited Use requirements, and to the Google Workspace Marketplace program policies. In short: data accessed via the scopes above is used only to provide the user-facing goal-seek feature, and is never transferred, sold, used for advertising, or used to train AI/ML models.

9. Revoking access and deleting data

You can revoke the add-on's access at any time at myaccount.google.com/permissions or uninstall it via Extensions → Add-ons → Manage add-ons in Google Sheets — the add-on then loses all access immediately. The small amount of data stored in a spreadsheet's document properties (section 4) is removed by deleting the spreadsheet, and it never leaves that file. The entries in the add-on's user properties stay with your Google account; they hold only cell references, the numbers you typed into the form and two counters, and older entries are replaced automatically. Because we hold no copy of your data, there is nothing further for us to delete; if you have any doubt, contact us (section 10) and we will confirm this for your case.

10. Support requests

If you contact us at kontakt@arbeitstyp.de, we use your email address and the content of your message solely to answer your request (legal basis: Art. 6(1)(f) GDPR — responding to your inquiry). Support emails are deleted once the request is resolved, unless a longer retention is legally required.

11. Your rights

Under the GDPR you have the rights of access, rectification, erasure, restriction, data portability and objection regarding personal data we process (which, per the above, is limited to support correspondence). You also have the right to lodge a complaint with a supervisory authority. For any request, contact kontakt@arbeitstyp.de.

12. Google's role

The add-on runs on Google Apps Script, inside Google Workspace. Google's processing of your data is governed by the Google Privacy Policy and your agreements with Google.

13. Changes

If the add-on ever changes in a way that affects data handling, this policy will be updated before the change ships, with a new effective date.