The answer in brief
To estimate annual subscription cost, multiply a weekly charge by 52, a monthly charge by 12, a quarterly charge by 4, and an annual charge by 1. Add only amounts in the same currency unless you convert them using a clearly dated exchange rate.
The annual cost formula
To compare software subscriptions with different billing schedules, convert each price to the same 12-month period:
- Weekly: price × 52
- Monthly: price × 12
- Quarterly: price × 4
- Annual: price × 1
Why monthly prices can hide the real commitment
A small monthly amount can look harmless on its own. Multiplying it by 12 makes it easier to compare with an annual invoice or quarterly plan. The annual equivalent is a comparison tool; it does not mean the provider will charge the full yearly amount at once.
Some services offer a discounted annual plan. Compare both the amount charged upfront and the effective annual cost. Note whether the price is introductory, when it changes, and whether a refund is available if you stop using the service.
Keep currencies separate
Do not add a $20 monthly subscription to a €15 annual subscription and label the sum as one currency total. First calculate the annual equivalent in each original currency. Convert only after selecting an exchange-rate source and a date, then label the converted figure as an estimate.
Foreign exchange rates move. Taxes may also be included in one vendor's price and added separately by another. Keep the original amount, currency, tax treatment, and conversion assumption so the result can be checked later.
A comparison table you can reuse
- Vendor and service name.
- Price per billing period and ISO currency code.
- Billing interval and annualized equivalent.
- Tax included, tax added, or unknown.
- Next renewal date and promotional-price end date.
- Usage level and the task the service supports.
For an accurate budget, include seat counts, usage-based charges, add-ons, and minimum commitments. A per-user price should be calculated using the number of paid seats, not just the displayed single-seat price.
Use the StackCut calculator
StackCut's free homepage calculator accepts three subscription entries and annualizes weekly, monthly, quarterly, and annual charges in the selected currency. It runs in your browser and does not upload or save the values entered. The full app supports manual entry and supported CSV import for a larger list.
Calculate your annual subscription spend or read the subscription tracker overview.
Annual cost calculation FAQ
Why multiply monthly prices by 12?
There are 12 months in a year, so multiplying a monthly price by 12 estimates the cost over 12 monthly billing periods.
Should I include tax?
Keep tax treatment consistent. Record whether the displayed price includes tax or whether tax is added at checkout. The actual amount may depend on location, customer type, and vendor tax handling.
Can I total different currencies?
Not directly. Calculate each annual amount in its original currency, then convert using a dated rate and label the result as an estimate.