Hong Life CalculatorsUnderstanding the free-to-paid conversion — concept and principle
Many software and subscription businesses let people start for free, either on a free plan (freemium) or a time-limited trial, and hope a share of them will pay. The free-to-paid conversion rate measures that share. This calculator divides the number of paying customers by the number of free users or trials in the same group, and shows the new monthly recurring revenue (MRR) those customers bring. It works with any currency.
How it is calculated
- Conversion rate = converted to paid ÷ free users or trials × 100
- New MRR = converted to paid × price per month
Free users / trials is the size of the starting group, ideally a cohort that signed up in the same period. Converted to paid is how many of that group became paying customers. Price per month is the average monthly amount each one pays.
The principle
Conversion is a proportion: out of everyone who entered the free stage, what fraction moved to the paid stage. Measuring by cohort matters, because users who signed up last week have not yet had a chance to convert. MRR multiplies paying customers by monthly price, which turns a percentage into money and links the funnel to revenue. If you know your conversion rate, you can work backwards: revenue goal ÷ price ÷ conversion rate gives the number of free sign-ups you need.
Worked example
- Conversion = 320 ÷ 8,000 = 0.04 = 4%.
- New MRR = 320 × $12 = $3,840.00.
- In a year, if all of them stay, that is 3,840 × 12 = $46,080 of recurring revenue.
- To double MRR at the same 4% rate, you would need about 16,000 free users.
How to read the result
What counts as good depends heavily on the model. Freemium products with an unlimited free plan often convert only a few percent of users, while trials that ask for payment details up front tend to convert a much higher share, because people self-select before they start. Compare yourself mainly with your own past cohorts and with products of the same type and price.
Common mistakes
- Mixing a fresh cohort with older users, which distorts the rate.
- Counting inactive or spam sign-ups in the free total.
- Treating MRR as guaranteed income while ignoring churn.
- Comparing freemium rates with card-required trial rates.
FAQ
Frequently asked questions
How long should I wait before measuring conversion?
At least until the trial ends, or for freemium a period long enough for most conversions to happen, often 30 to 90 days. Use the same window every time.
Should I use annual plans in MRR?
Yes, divide the annual price by 12 to get its monthly equivalent.
How can I raise the conversion rate?
Make the paid value clear, guide new users to their first success quickly, and test the limits of the free plan. Measure each change with a controlled test.
Sources: Kohavi, Tang & Xu — Trustworthy Online Controlled Experiments (Cambridge University Press, 2020)