How to Use DeepSeek or Kimi AI in Excel
August 14, 2026 · 7 min read
Every major AI lab now ships an Excel add-in, and every one of them is locked to that lab's own models at that lab's own price. If you would rather run a model that costs cents instead of a subscription, you need an add-in that accepts your own API key. This guide shows how to do that with DeepSeek or Kimi, what it actually costs, and where the approach has real limits.
Why bring your own key at all?
The complaint that shows up in review after review of AI spreadsheet tools is not the sticker price. It is the meter: opaque credit packs, surprise per-token charges, and usage limits that reset on someone else's timer. Bringing your own key removes the meter entirely. You pay your provider directly at their published rate, and the add-in charges a flat fee for the software.
DeepSeek and Kimi are the two providers where this matters most, because both are dramatically cheaper than the frontier subscriptions most Excel add-ins resell.
What each provider gives you
DeepSeek is pay-per-token, and the tokens are cheap enough that a complete three-statement model usually costs a few cents. There is no monthly minimum. Its API is OpenAI-compatible, which means the add-in can call it directly from your machine. Nothing routes through anyone else's server.
Kimi Code is a flat subscription: $19 per month, with an allowance built for heavy daily coding-style work. If you live in your models all day, flat-rate beats per-token. One thing worth knowing: today, EBITDAI is the only Excel add-in that runs on a Kimi Code plan, so if you want that flat-rate allowance inside your workbook, this is currently the way to get it.
Setting it up, step by step
- 1Install the EBITDAI add-inOpen Excel, go to the Insert tab, choose Get Add-ins, and search for EBITDAI. It works in Excel on the web and on the desktop, on both Windows and Mac.
- 2Get an API key from DeepSeek or KimiFor DeepSeek, sign in at platform.deepseek.com and create a key under API keys. For Kimi, open the Kimi Code console at kimi.com/code/console and create a key. Copy it immediately, since providers show a key only once.
- 3Connect the key in the task paneOpen the EBITDAI pane in Excel, pick your provider, and paste the key. EBITDAI verifies it with a single test call. The key is stored on your device, not on our servers.
- 4Describe what you want in plain EnglishType a request such as 'Build a 3-statement model for a SaaS business with $2M ARR growing 40%' or 'Explain what is driving the total in column F'. The agent reads your actual cells and writes the result into the workbook.
The full walkthrough with troubleshooting lives in the documentation.
What it actually costs
| Setup | Monthly | What limits you |
|---|---|---|
| EBITDAI + DeepSeek | $15/month (Pro) | Nothing. You pay per token |
| EBITDAI + Kimi Code | $15 Pro + $19 flat = $34 | Kimi's subscription allowance |
| Claude for Excel | $20 Pro, $100+ Max | Plan usage limits, Claude models only |
| ChatGPT for Excel | Free tier, $20 for real limits | Tier caps, GPT models only |
| Microsoft 365 Copilot | $30 per seat | Licensing, Microsoft-hosted models only |
Provider pricing as of August 2026. DeepSeek estimates are measured on EBITDAI's own benchmark model builds; your usage will vary with model size and how much you iterate.
When this is the wrong choice
If your organization requires that data stay inside a Microsoft tenant, Copilot is the right answer and no amount of cost saving changes that. If you have never touched an API key and never want to, a first-party add-in that logs in with an account you already have will be less friction. And if you want the strongest available frontier reasoning regardless of price, pay for it. Cheaper models are cheaper for reasons that occasionally show up in hard problems.
Frequently asked questions
Can you use DeepSeek in Excel?
Yes. DeepSeek has no official Excel plugin, but its API is OpenAI-compatible, so an add-in can connect to it with your own API key. EBITDAI does this: you paste a DeepSeek key into the task pane and the agent reads and edits your workbook using your account. Because you pay DeepSeek directly at their per-token rates, a full financial model typically costs a few cents.
Can you use Kimi (Moonshot) in Excel?
Yes, through EBITDAI, two ways. A flat-rate Kimi Code subscription powers your Excel work with no per-token charges, EBITDAI is the only Excel add-in that runs on one. Or connect a pay-as-you-go key from the Moonshot Open Platform: same k3 model, metered billing, no waitlist.
How much does it cost to run AI in Excel this way?
EBITDAI is $15/month on Pro, with 7.5x more usage than Lite across every included model; 20% off annually. Layering your own $19/month Kimi Code subscription on top of Pro ($34 all-in) is the most cost-effective way to run EBITDAI all day. Your own DeepSeek key charges per token, usually cents per model, and own keys come with Pro. EBITDAI adds no markup to those tokens and runs no credit system.
Is this different from Copilot or Claude for Excel?
Those are excellent products, but each is locked to its vendor's own models and pricing: Microsoft 365 Copilot is $30 per seat, and Claude for Excel requires a Claude plan starting at $20/month. Neither lets you bring your own API key or choose a cheaper model. That model choice is the entire point of EBITDAI's approach.
Is my spreadsheet data safe?
On paid plans, your workbook is never stored by EBITDAI. Free-plan conversations are logged and reviewed to improve the product. With DeepSeek, the add-in calls the provider directly from your machine, so nothing touches our infrastructure at all. Pay-as-you-go Kimi keys also connect directly from your machine. With Kimi Code, whose API cannot be called from a browser, requests pass through a stateless relay that forwards them and retains nothing: no prompts, no workbook content, no keys.
Related reading: dedicated setup guides for DeepSeek in Excel and a Kimi Code subscription in Excel, why we rebuilt EBITDAI around your own AI account, EBITDAI vs Copilot in Excel, and how your data is handled.