Calculators
Free Form Backend Cost Calculator
Compare two form backend plans by monthly price, included submissions and overage charges against your expected volume. See which is cheaper each month.
Your result
Plan A: 15 · Plan B: 15
Each plan: base monthly price + max(0, usage − allowance) × unit overage price. Enter actual terms; taxes and annual discounts are excluded.
A zero overage price means free additional usage in this model. For a hard submission cap, compare plans only within that cap.
How to use this tool
- Enter the submissions you expect each month.
- Enter each plan's monthly price, included submissions and price per extra submission.
- Compare the monthly cost of the two plans and change the volume to find the break-even point.
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Form backend cost calculator
questions.
What should I count as a submission?
Every accepted form post, including spam that gets through, counts toward most plan allowances. Add a margin for launches and seasonal spikes.
Is Form Koi free for small sites?
Yes. The free plan covers a generous number of submissions each month with spam filtering and email notifications included. See the pricing page for the current allowance.
Is anything I enter saved or sent to Form Koi?
No. Everything you type or upload stays in this browser tab and is processed locally. Copy or download anything you want to keep before leaving the page.
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