Honor box shrink calculator
How much is going missing from my self-serve stand?
Showing for United States
Expected, from what went out
—
- Collected more than expected
- —
- Shrink (missing as a share of what was expected)
- —
- Expected, from what went out
- —
- Missing over the season, at this rate
- —
- Result
- —
Missing money can be theft, but also mistakes, giveaways, stock thrown out or a miscount. This is a count, not an accusation.
No study measures typical losses at self-serve stands, so there is no figure to compare with. Compare your own periods with each other.
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 much is going missing from my self-serve stand?"
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
For each item, the units that went out are the units at the start, plus any added during the period, less the units left at the end. What you should have collected is those units times each item's price, added up across items. What is missing is that expected amount less all the money you actually collected for the same items and period: the cash in the box plus any card or app payments. Shrink is what is missing as a share of what was expected. A season figure multiplies what is missing by the number of periods like this one in your season, and is shown only when money went missing. If you collected more than expected, the result says so and nothing is projected.
A worked example
Example numbers only; use your own. You put out 40 jars of jam at 6.00 and 4 are left at the end, so 36 went out and you should have 216.00. The box holds 180.00, so 36.00 is missing: 16.67 percent of what you were owed. Across three items worth 304.00 with 265.00 collected, 39.00 is missing, or 12.83 percent; over a season of 20 weeks like that, that is 780.00.
Nothing you type here is saved.