CSA members and acres planner
How many CSA members do I need, and how much ground does that take?
Showing for United States
Members you need
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- Revenue from those members
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- Profit
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- Ground needed (same unit as your yield)
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Members are rounded up to a whole member, and ground up to two decimals, so neither falls short. Count shares as full shares: two half shares are one.
Shares per acre or hectare depend on your crops, beds, weeks and share size. Use your own records; no published figure is reliable enough to fill in for you.
Use the same unit, acres or hectares, for both ground figures.
Members your ground can feed
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- Revenue from those members
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- Members needed to cover costs
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- Profit
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Members are rounded down, because ground cannot feed part of a member.
Shares per acre or hectare depend on your crops, beds, weeks and share size. Use your own records; no published figure is reliable enough to fill in for you.
Use the same unit, acres or hectares, for both ground figures.
Enter your numbers to see the result.
Planning a farm stand, a CSA or a shop? TallyTill is free to start.
Get started with TallyTill for freeUse this calculator in an AI chat
You can ask Claude, ChatGPT or another AI app to work this out for you, and this calculator opens right inside the chat. You connect TallyTill to your AI app once. It is free, and there is no account and no sign-in.
AI apps call add-ons like this connectors, apps or MCP servers. They all mean the same thing: a way for the AI to use a tool someone else made.
1. Copy this address
2. Add it to your AI app
Claude (claude.ai and the Claude desktop app)
- Open Customize, then Connectors.
- Press + Add, then Add custom connector.
- Name it TallyTill calculators, paste the address and press Continue.
- Under Authentication choose No sign in, then press Add.
- In a new chat, press + at the bottom left, choose Connectors and switch TallyTill calculators on.
On Claude's free plan you can add one custom connector.
ChatGPT
- In Settings, turn on Developer mode. OpenAI moves this switch from time to time; it is usually with the settings for apps and connectors.
- Add a new connector (ChatGPT may call it an app), paste the address and choose No authentication.
- In a new chat, choose TallyTill from the tools menu, or type @ and pick it.
Not every ChatGPT plan lets you add your own connector. If you cannot find the option, your plan may not include it.
Using another AI app? Look in its settings for MCP, add the address as a remote server, and choose no sign-in.
3. Ask your question
Say "use TallyTill", so the AI uses the calculator instead of doing the sum itself. For example:
"Use TallyTill: How many CSA members do I need, and how much ground does that take?"
What you will see
- The calculator opens in the chat with the numbers you gave already filled in. Change any number and the answer updates.
- If a number is missing, the box is highlighted, or the AI asks you for it in plain words.
- The answer links back to this page, so you can check the working.
- The first time, your AI app asks if it may use TallyTill. Choose Allow.
The calculators take numbers only. They never ask for your name, your email or a password.
How this is worked out
Members needed are your season costs, plus any profit you want, divided by the price of a full share, rounded up to a whole member. Revenue is those members times the share price, and profit is revenue less costs. Ground needed is the members divided by the shares one acre or hectare of your ground produces, rounded up to two decimals. Starting from ground, the members it can feed are the ground times the shares it produces, rounded down to a whole member, because ground cannot feed part of a member. Use the same unit, acres or hectares, for both ground figures.
A worked example
Example numbers only; use your own. With season costs of 45,000 and a share price of 643, you need 45,000 ÷ 643 = 69.98, so 70 members, who bring in 45,010.00. If your own records show 20 shares an acre, 70 members need 3.50 acres. Starting from 2.3 acres at 18 shares an acre, the ground feeds 41 members.
Nothing you type here is saved.