For people who paste spreadsheets into ChatGPT or Claude
Excel & CSV to clean Markdown or JSON your AI reads correctly.
Drop an .xlsx or .csv and get a tidy Markdown table or JSON: real header row, every sheet labelled, $3,480 kept as you see it. SheetMD is a web app (PWA) that runs in your browser and works offline. Your files never leave your device.
$39 $29 lifetime early-bird. Waitlist only: no payment is taken and no card is asked for. Not launched yet.
- Drop an Excel or CSV file. Nothing is uploaded.
- Check the preview, then pick Markdown or JSON.
- Copy in one click and paste into ChatGPT, Claude or your notes.
Sound familiar?
Pasting cells breaks the table
Copying a range from Excel gives you tab-separated text. On wide sheets it's easy for headers and values to drift apart, and the other sheets don't come along at all.
Uploading to a converter site
Salary sheets, client lists and pipelines shouldn't go to a random server just so you can get Markdown out.
Doing it again next week
The same weekly export, cleaned up by hand every time before it goes into a chat.
Example output
Real output from the prototype for the two-sheet demo file above (merged title row lifted out, blank row dropped, formulas shown as their values).
## Q3 Pipeline *Q3 2026 Sales Pipeline (EMEA + NA)* | Account | Region | Owner | Close date | Seats | Price / seat | Total | | --- | --- | --- | --- | --- | --- | --- | | Acme Logistics | EMEA | Priya S. | 2026-07-14 | 120 | $29 | $3,480 | | Northwind GmbH | EMEA | Jonas K. | 2026-08-02 | 45 | $99 | $4,455 | | Blue Harbor Inc. | NA | Maria L. | 2026-08-19 | 300 | $24 | $7,200 | | Kestrel Health | NA | Maria L. | | 18 | $149 | $2,682 | | Orbit Retail, Ltd. | EMEA | Priya S. | 2026-09-09 | 62 | $49 | $3,038 | | Pinecone Labs | NA | Dev R. | 2026-09-27 | 9 | $199 | $1,791 | | Total | | | | 554 | | $22,646 | ## Notes | Account | Status | Next step | | --- | --- | --- | | Kestrel Health | At risk | Legal review; no close date yet | | Blue Harbor Inc. | Committed | Send order form \| PO pending | | Pinecone Labs | Upside | Pilot ends Sep 20 |
[
{
"sheet": "Q3 Pipeline",
"title": "Q3 2026 Sales Pipeline (EMEA + NA)",
"columns": [
"Account",
"Region",
"Owner",
"Close date",
"Seats",
"Price / seat",
"Total"
],
"rows": [
{
"Account": "Acme Logistics",
"Region": "EMEA",
"Owner": "Priya S.",
"Close date": "2026-07-14",
"Seats": "120",
"Price / seat": "$29",
"Total": "$3,480"
}
]
}
]Also planned: Excel .xls, OpenDocument .ods, and basic Word, PowerPoint, PDF (text-based), RTF and EPUB to Markdown.
Verify it yourself: open your browser's DevTools Network tab, or turn on airplane mode, then convert. Nothing is uploaded. The app will ship with a strict Content-Security-Policy and no third-party scripts.
Planned Pro features planned, not built
None of these exist yet. Tell me which ones matter to you (waitlist question or the feedback board) and I'll build those first.
- Token counter so you know if it fits before you paste
- Auto-split big sheets into chunks that fit a context window
- Column and sheet selection before export
- PII masking (emails, phone numbers, names) before you paste into an LLM
- Formulas vs values, your choice
- Merged-cell handling options
- Conversion history stored on your device
- Batch export of many files to .md (Obsidian-friendly)
Pre-launch early-bird
SheetMD lifetime
$39 $29 once
- Excel / CSV → Markdown or JSON, in your browser
- Works offline, installable web app (PWA)
- The planned Pro features above as they ship
- All 1.x updates, no subscription
This is a waitlist, not a purchase. No payment is taken and no card is asked for. I'll email you when it launches with the $29 price held for you. Regular price after launch: $39.
Timeline: I build it only if enough people reserve. Target launch is about 3–4 weeks after the waitlist hits its goal.
Join the waitlist
One email from me when it launches, plus maybe one asking what you'd use it for. No spam, and you can unsubscribe any time.
Tell me what's missing
Which feature would make this worth paying for? Ask, suggest or tell me it's a bad idea on the public feedback board.
Open the public feedback board →Who's building this
Built by Himanshu Rathore, an independent solo developer. I'm testing demand in public before writing the app, and I'll share what I learn either way. Questions or ideas: @himanshu19890 on X or the feedback board.
FAQ
Is it built yet?
No. I'm checking whether enough people want it before I build it. The conversion engine works (the recording above is a real prototype), but the finished app doesn't exist yet. Reserving the early-bird price just puts you on the waitlist with $29 held for you.
Am I paying anything now?
No. It's a waitlist only. I don't take payment and I don't ask for a card. When SheetMD launches I'll email you, and you can buy it at the $29 early-bird price (regular price $39) or ignore the email.
What exactly is it?
A web app (PWA) that runs in your browser. You can install it like an app and it works offline once loaded. No extension and no account are needed to convert files.
How can it be local?
The converter is compiled to WebAssembly and runs inside your browser tab, like a calculator app. Your file is read into memory on your device and converted there. Nothing is uploaded. You can check this yourself in DevTools or with airplane mode on.
Why not just use a free converter?
If a free converter works for you, use it. SheetMD is built for getting spreadsheets into an LLM safely and accurately: it never uploads your file, and it prepares the data for the model rather than just changing the format. That means a token count before you paste, splitting big sheets into chunks that fit the context window, picking only the columns and sheets you need, masking emails, phone numbers and names first, and clear choices for formulas and merged cells. Those are planned features, and the waitlist tells me which ones to build first.
Scanned PDFs?
No. Image-only pages need OCR, and v1 won't do it. I'd rather say so now.
Privacy
Your documents: the app converts files on your device. I never receive, store or see their contents.
This page: I use privacy-friendly, cookie-free analytics to count visits, button clicks and which link brought you here (UTM tags). I don't use advertising trackers.
Your email: if you join the waitlist or reserve the early-bird price, I store your email, your answer to the optional question and the link that brought you here. I use them only to tell you about SheetMD. I never sell them. Email me to have them deleted.
Contact: himanshu19890@gmail.com