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Side project budget template and planner

Plan what the project will cost before you buy anything. Enter each cost, say whether it is billed monthly or yearly, and see the monthly equivalent and the yearly cash due.

By Matt Warcholinski, co-founder of Brainhub · Updated 23 October 2026

Not financial or tax advice. This is a planning aid. It uses the numbers you type and nothing leaves your browser.

Planned budget or actual costs?

Do not settle up from the plan. Settle up from real payments, because prices change and bills arrive late.

The planner

Enter your costs. Leave unused rows empty. Each currency is totalled separately and never added to another.

ItemAmountCurrencyBilled

Two numbers that matter

A worked example (illustrative)

The inputs below are made up for the demonstration. They are not real vendor prices.

ItemBilledAmount (EUR)Monthly equivalent
Domainper year242
Hostingper month2020
Dev toolper month3030
Total52 per month, 624 per year

Before you commit to a cost

  1. Write the renewal date next to each yearly cost so it does not surprise you.
  2. Note how to cancel. Check the provider's current terms before you rely on a refund.
  3. Agree a spending line that needs both of you. The team charter has a place for it.
  4. Log the decision in a decision log.

Do it with AI

Turn a tool list into a budget

Paste your tool list into Claude or ChatGPT. Do not include card numbers or passwords.

I run a side project with a partner. Below are the tools we plan to use with the price and billing period I know. Do not guess prices; if one is missing, ask me.
Output one line per tool: item, amount, currency, billed per month or per year.
Then give: the monthly equivalent per currency, the yearly cash due per currency, and the first-month cash if any yearly bill is paid up front.
Keep currencies separate. Do not convert between them.
Tools:
[PASTE HERE]

Frequently asked questions

How much should a side project budget be?

It depends on your goal and what you can afford to lose. Set a cap before you start, split it between you, and review it at each milestone.

How do I compare a yearly and a monthly cost?

Divide the yearly cost by 12 to get a monthly equivalent. Keep in mind that the yearly bill is paid in one go.

Does the planner store my data?

No. It runs in your browser and nothing you type is sent or saved.

What about different currencies?

The planner totals each currency separately. If you want a single total, convert at a rate you both agree on and note the date.

Related tools

Log each real bill once and see who owes whom, always up to date.

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