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LLM API Keys

Captain EPM uses AI to help you analyze EPM data, write formulas, and automate planning tasks directly in Excel. To enable this, you connect your own API key from Anthropic, OpenAI, or Google. This guide walks you through the full setup in under 5 minutes.

Before You Start: API Access Is Separate From Consumer Plans

This is the most common point of confusion — read this first.

A consumer subscription does not include API access. They are completely separate products, billed separately.

PlanWhat it gives youWorks with Captain EPM?
Claude Pro / Max ($20–$200/mo)Access to claude.ai web and mobile No
ChatGPT Plus ($20/mo)Access to chat.openai.com No
Gemini Advanced ($20/mo)Access to gemini.google.com No
Anthropic API (pay-as-you-go)Programmatic access via API key Yes
OpenAI API (pay-as-you-go)Programmatic access via API key Yes
Google AI API (pay-as-you-go)Programmatic access via API key Yes

Captain EPM uses the API, which is billed separately and consumption-based — you only pay for what you actually use.

What Will This Actually Cost?

Real numbers based on public API rates (May 2026), using Claude Sonnet 4.6 — our recommended default model for FP&A work.

Cost per task

Summarize a 500-row data slice~$0.04
Generate a 10-formula breakdown~$0.04
Analyze variance across 4 scenarios~$0.09
Full chat session (20 messages)~$0.30

Monthly cost by usage

Light~20 tasks/week
~$3/mo
Moderate~80 tasks/week
~$12/mo
Heavy~200 tasks/week
~$30/mo
Most FP&A users land in the Moderate tier at around $10–$15/month with Sonnet 4.6 — less than a single consumer subscription, and you only pay for what you use. Set a monthly spending limit in your provider's console to cap costs.

Pricing shown reflects public API rates as of May 2026 and may change. Verify current rates with your provider before production use.

How We Protect Your API Key

🔒

Encrypted locally with Windows DPAPI

Your API key is encrypted on your machine using Windows Data Protection API. The encryption is tied to your Windows user account — no other user on the same computer can decrypt it.

🚫

We never see your key

Your key never leaves your machine, except in direct outbound HTTPS calls from Captain EPM to your chosen AI provider. It is never sent to Captain EPM servers, never logged, never transmitted to any third party.

🛡️

Recommended best practices

  • Create a dedicated key labeled "Captain EPM" so you can revoke it independently of other apps.
  • Set a monthly spending limit in your provider's console.
  • If you leave your organization or change machines, revoke the old key from the provider console.
📋

Enterprise note

If your organization has an Anthropic, OpenAI, or Google Cloud enterprise account, use a key issued under that account. Captain EPM works with both individual and enterprise keys.

Step 1 — Choose Your AI Provider

Captain EPM supports multiple AI providers. Pick one to start — you can configure others later.

A
Anthropic (Claude)
⭐ Recommended for FP&A

Best for complex financial reasoning, long-context analysis, and precise instruction following.

O
OpenAI (GPT)

Best for speed, broad tool ecosystem, and code/formula generation. Default: GPT-4o.

G
Google (Gemini)

Best for cost-conscious users and multimodal tasks. Generous free tier for getting started.

Not sure which model to pick? Start with Claude Sonnet 4.6 — best balance of capability and cost for FP&A work at $3/$15 per 1M input/output tokens. Upgrade to Opus 4.7 only if you're hitting limits on complex multi-step analyses.

Step 2 — Create Your API Key

A
Anthropic (Claude)

  1. Go to the Anthropic Console . Sign in or create a developer account — this is separate from a claude.ai consumer account, though you can use the same email.
  2. Navigate to Settings → Billing. Add a payment method and set a monthly spending limit (we recommend starting at $25).
  3. Go to Settings → API Keys → Create Key. Name it "Captain EPM".
  4. Copy the generated key (starts with sk-ant-...). You will only see it once.
Available models: Sonnet 4.6 ($3/$15 per 1M tokens) — recommended · Opus 4.7 ($5/$25) — premium · Haiku 4.5 ($1/$5) — budget

O
OpenAI (ChatGPT)

  1. Log in to the OpenAI Developer Platform .
  2. Navigate to Settings → Billing. Add credits or enable auto-recharge, and set a monthly usage limit. OpenAI requires prepaid credits before keys will work.
  3. Go to API Keys → Create new secret key. Name it "Captain EPM".
  4. Copy the generated key (starts with sk-proj-...). You will not be able to view it again.

G
Google Gemini

  1. Navigate to Google AI Studio . Sign in with your Google account.
  2. Click Get API Key → Create API Key in new project (or select an existing Google Cloud project).
  3. For production use beyond the free tier, enable billing on the linked Google Cloud project.
  4. Copy the generated key (starts with AIza...).

D
DeepSeek API

  1. Log in to the DeepSeek Platform .
  2. Navigate to the API Keys tab.
  3. Click Create new API key.
  4. Copy the generated key (starts with sk-).

X
xAI API (Grok)

  1. Log in to the xAI Console .
  2. Navigate to the API Keys section.
  3. Click Create API Key.
  4. Copy the generated key (starts with xai-).

K
Moonshot API (Kimi)

  1. Log in to the Moonshot Platform .
  2. Navigate to the API Keys page in the console.
  3. Click Create API Key.
  4. Copy the generated key (starts with sk-).

Step 3 — Configure the Add-in

  1. Open Microsoft Excel and navigate to the Captain EPM ribbon tab.
  2. In the AI group, click Configure AI (or Settings → Providers tab).
  3. Select your provider from the dropdown.
  4. Paste your API key into the designated field.
  5. Click Test Connection. Captain EPM will validate your key before saving.
    Success — your key is active and ready.
    401 Unauthorized — key is invalid, mistyped, or revoked. Generate a new one.
    429 Rate Limited / No Credit — add billing or credits to your provider account.
    Network Error — check your firewall, VPN, or proxy settings.
  6. Select your default model from the dropdown. If unsure, start with Claude Sonnet 4.6.
    Optional: expand Advanced Settings to adjust Temperature (default 0.3 for analytical tasks) and Max Tokens (default 4096).
  7. Click Save. The AI panel in the add-in is now enabled.

Frequently Asked Questions

Do I need a Claude Pro / ChatGPT Plus subscription to use Captain EPM?

No. Captain EPM uses the API, which is billed separately. A consumer subscription does not provide API access and is not required.

How much will I spend on API costs?

Most FP&A users spend $3–$20/month depending on the model and usage volume. See the cost estimator above. Set a monthly spending limit in your provider's console to cap it.

Is my API key secure?

Yes. Keys are encrypted locally using Windows DPAPI, tied to your Windows user account. They never reach Captain EPM servers and cannot be decrypted by any other user account on your machine.

Can I use multiple providers?

Yes. Configure each provider separately under Settings → Providers. You can switch between them per conversation.

My organization has an enterprise AI account. Can I use that?

Yes. Use the API key issued under your organization's enterprise account. Captain EPM works with both individual and enterprise keys.

Which model should I pick if I'm not sure?

Start with Claude Sonnet 4.6 — best balance of capability and cost for FP&A work. Upgrade to Opus 4.7 only if you need more power for complex multi-step analyses. Use Haiku 4.5 if you run high volumes of routine tasks and want to minimize cost.