Separate the plan from the extra usage
First identify how the service charges: a subscription, credit packs, usage billing, or a combination. Use the calculator on our homepage only for a monthly plan with whole credit packs. It does not model every billing system or quote WantYou.ai prices.
A worked example with invented prices
Suppose a plan costs $12 per month and includes 600 credits. You expect to use 1,050 credits. Each extra pack contains 300 credits and costs $5. The 450-credit gap requires two packs, so the charge is $12 + $10 = $22 before tax. You purchased 150 more credits than you needed; whether they expire or roll over is a separate question.
Extra credits = max(0, expected use − included credits) Packs needed = round up(extra credits ÷ credits per pack) Estimated charge = monthly plan + packs needed × pack price
Why two similar prices can mean different bills
| Displayed detail | What you still need |
|---|---|
| A monthly equivalent for an annual plan | The full amount due today and the renewal period. |
| Included credits | The credit cost of the actions you actually use. |
| A promotional price | The later renewal price and when it begins. |
| A free allowance | Its limits, reset timing, and whether a payment method is required. |
Estimate from a representative session
If the service shows a usage meter, record its value before and after a typical session, with the types of actions used. A session containing images or voice may not resemble text-only use. Scale your observation to your expected number of sessions; do not assume one credit equals one message.
Set the ceiling before the top-up
Choose a total you are comfortable spending. If the estimated plan plus whole packs exceeds it, reduce optional usage or consider another billing arrangement. Check whether top-ups are manual or automatic. Verify cancellation, renewal, and refund terms directly with the provider; this guide has not checked a paid checkout.
Use the monthly calculator with published values. If a required value is unknown, the answer is unknown; entering zero would produce a misleading estimate.
