Data control for AI assisted work
AI for Excel.
Control what
you share.
Ask for the formula you need. Mark private columns, review the exact request, and run the checked result in Excel without treating every cell as model input.
Excel first. Explore the open-source project ↗
Watch NymForm move through
the Excel workflow.
The video plays from Vimeo. Pressing play loads Vimeo’s player, which receives your IP address. Privacy notice
What the video shows, step by step:
- Open Ask and describe the formula you need: "Total Amount per Region, one row per region".
- On Columns, mark Customer and Email as Keep private. The request preview shows stand-ins such as PERSON_001 and EMAIL_001; the worksheet cells stay unchanged. The video’s in-sheet masking is a conceptual animation.
- Return to Ask and choose Include sample rows. Region and Amount will be sent as they are.
- Inspect What gets sent: names and emails appear only as stand-ins; the other sample values stay visible. The check reports no private values found.
- Send (simulated in this preview), review the returned formula and choose Insert formula. The totals per region appear beside the data, and the original cells stay unchanged.
PRODUCT PREVIEW. Scripted product preview, not a live recording. All workbook data is synthetic. The navigation, screen names, privacy controls, request preview, Send step, formula result, and Insert formula action are modelled on the current alpha workflow. Captions in the video explain each step. No live model request is made in this preview.
A deliberate data boundary
Useful context.
Less exposure.
NymForm helps you get AI assistance without automatically sharing every cell value. You choose the mode and private columns. You review the request before it is sent.
Starting in Excel. Built toward more control over how AI fits into everyday work.
Structure only
A description of your worksheet. No data cell values in the request.
Sample rows
Values in columns you mark private are replaced with stand-ins or selected treatments. Unmarked sample values can still be sent.
What NymForm is, in plain answers.
- What is NymForm?
- NymForm is an open-source add-in for Microsoft Excel. You select a range, mark the columns that are private and ask for a formula in plain language. NymForm sends an AI model a description of your data's structure, or sample rows with private values replaced by stand-ins, shows you the exact request before it is sent, checks the formula that comes back, and writes nothing until you choose Insert formula. Getting started
- Does NymForm send my spreadsheet to the AI?
- Not as it is. In structure-only mode the request holds headers, types and counts and no cell values. In sample-rows mode, values in the columns you mark private are replaced with stand-ins such as PERSON_001 before sending; values in columns you don't mark private are sent as they are. Headers, sheet names, notes and your question are always sent, and you can read the exact request on What gets sent before you choose Send. What AI models see
- Which AI model does NymForm use, and do I need my own key?
- NymForm sends requests to OpenRouter with an API key you create and enter yourself, so you keep control of spending and settings. The default model is openai/gpt-6-luna, requested with OpenRouter's zero-data-retention routing, and you can enter another OpenRouter model ID. The key stays in memory for the session only. Security & data flow
- Is NymForm free and open source?
- Yes. The source code is published on GitHub under the GNU AGPL-3.0-only license, and the hosted alpha build is served from GitHub Pages so you can sideload it into Excel without running a local server. You pay only for your own OpenRouter usage. Open source & licensing
- Which versions of Excel does NymForm work with?
- Excel on the web, Excel for Windows and Excel for Mac with the Excel JavaScript API 1.9 or later, which current Microsoft 365 versions have. The hosted alpha has been run in Excel for Mac and the add-in has been used in Excel on the web; Excel for Windows hasn't been checked yet. Alpha limitations
- Can I use NymForm with sensitive data?
- NymForm is alpha software for evaluation: try it with synthetic or non-sensitive data first. It is a technical control that reduces what an AI model sees, not a compliance certification, and its limits are documented plainly, including short values, unmarked columns and small groups. Whether a use meets your legal or organizational requirements is your decision. Terms of use
Enterprise / coming soon
NymForm for teams.
Bring more deliberate AI workflows to organizations working with sensitive spreadsheet data. Enterprise deployment and commercial licensing are in development.
No pricing or deployment commitments yet. Join the list to hear when the enterprise offering is ready.
Hear when it launches.
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Early access
Be there for
the first release.
Get notified when the Excel alpha is ready. Product progress and early invites. Nothing extra.
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