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FenRelease 2026.10.1

Tools ​

These calculators are in the menu under Tools. Except for the Breakdown Calculator, they don't save what you type and don't read your wallets. You enter the numbers each time.

Other tools have their own pages: Financial Goals, Merchant Summary, Receipt Scanner and Document Locker, and Net Worth Tracker and Debt Payoff Planner.

Breakdown Calculator ​

Split an amount into percentages, for example to set aside taxes and savings from a payment.

  1. Enter the Revenue Amount.
  2. Each line has a name and a whole-number percentage. Fen shows the amount for each line.
  3. Tap + in the toolbar to add a line. Tap a name or percentage to change it.

The Total shows the combined percentage. Fen warns you if it's over or under 100%. Your lines are saved on this device and are there the next time you open the calculator.

Templates ​

Tap the folder button to open Templates.

  • Tap a default template to load it. This replaces your current lines.
  • Tap Save Current and enter a name to save your current lines as your own template.
  • Your templates appear under Saved Templates. Tap one to load it, or swipe left to delete it.
Default templateLines
Business RevenueOperating Costs 40%, Taxes 25%, Profit 20%, Growth Investment 10%, Emergency Fund 5%
Freelancer RevenueTake-home Pay 50%, Taxes 30%, Business Expenses 10%, Retirement 5%, Professional Development 5%
50/30/20 BudgetNeeds (Housing, Bills, Food) 50%, Wants (Entertainment, Shopping) 30%, Savings & Debt Payment 20%
Savings PriorityEmergency Fund 40%, Retirement 30%, Short-term Savings 20%, Investment 10%
Debt PayoffHigh Interest Debt 50%, Medium Interest Debt 30%, Low Interest Debt 15%, Emergency Fund 5%
Investment PortfolioStocks 40%, Bonds 30%, Real Estate 20%, Cash 10%

Loan Calculator ​

Work out the monthly payment on a loan. Enter:

  • Loan Amount
  • Down Payment
  • Interest Rate: the annual rate. Starts at 5%.
  • Loan Term (Months): starts at 60.

Results shows the Monthly Payment, the Principal Amount (loan amount minus down payment), the Total Interest over the term, and the Total Cost (principal plus interest).

Cash Flow Forecaster ​

Project your balance over the next 12 months. Enter your Current Balance, Monthly Revenue and Monthly Expenses.

  • Estimated Runway shows how many whole months until your balance reaches zero if expenses are higher than revenue. If revenue covers expenses, it shows Infinite.
  • 12 Month Projection lists your projected balance at the end of each of the next 12 months.

Tax Estimator ​

Get a rough estimate of tax owed on business income. Enter Revenue, Expenses/Deductions and a Tax Rate. Type the rate or use the slider, which goes from 0% to 50% in half-percent steps. The rate starts at 25%.

Estimation shows:

  • Taxable Income: revenue minus expenses, never below zero.
  • Estimated Tax: taxable income × your rate.
  • Net Profit: taxable income minus estimated tax.

The estimator uses a single flat rate. It isn't tax advice, so check your real rate with a tax professional.

Invoice Generator ​

Make a simple invoice and share it as a PDF. Open the menu and tap Invoice Generator.

  1. Under Details, enter the Client Name, the invoice number (starts as INV-001) and the Date.
  2. Under Items, tap + to add a line. Enter a description, quantity and rate. Fen calculates each line total and the invoice Total.
  3. Check the preview at the top of the screen.
  4. Tap the share button in the toolbar to send or save the invoice as a PDF.

Invoices aren't saved in Fen. Share or save the PDF before you leave the screen.

TIP

The Cash Flow Forecaster and Tax Estimator show amounts in your device's region currency while you type, rather than the symbol you picked in Settings. Results use your chosen symbol.

Odd Omens is a one-person studio building privacy-first software.