Free Tools

Free calculators for the numbers marketers get asked about most. Nothing you type leaves your browser.

Analytics

UTM builder

Tag campaign links so GA4 puts traffic in the right channel. Values are cleaned as you type: lowercase, no spaces. Nothing you type leaves your browser.

Where the click comes from
The type of channel
Keep one naming pattern, e.g. topic-quarter
Paid search keyword
Ad or link variant
Your tagged link

    Stack building

    CAC and payback calculator

    Customer acquisition cost is everything you spent to win customers, divided by how many you won. Payback is how long their gross margin takes to repay it.

    Ads, tools, content, agencies
    Salaries, commissions, sales tools
    Customer acquisition cost-
    Payback period-
    LTV : CAC-

    Rule of thumb for subscription businesses: payback under 12 months and LTV:CAC of 3 or more.

    CRO

    A/B test sample size calculator

    How many visitors each variant needs to detect the lift you care about, at 95% confidence and your chosen power.

    Relative, so 20% takes 3% to 3.6%
    Statistical power
    Visitors needed per variant-
    Total visitors-
    Test length-