Date tools for people. Date infrastructure for products and teams.
Use Calcadian free in your browser, or add the same date logic to your website, API workflow or business process.
Plans
Free
For everyday calculations and trying the API.
$0
- Every calculator on the site, with no account
- Branded embeds for any page you run
- 500 API requests a month
- 1 API key
- MCP Basic for compatible AI assistants
Pro
For developers, publishers and small teams using Calcadian in a product or website.
$12a month
Or $99 a year.
- 10,000 API requests a month
- 20 saved widgets, white-label, on 3 licensed domains
- 5 Business Calendars with your holidays and working week
- Batch up to 5,000 rows a job
- Calculation Reports as PDF, CSV or JSON
Checking your account…
Business
For teams running higher-volume date calculations, multiple calendars and multiple integrations.
$49a month
Or $449 a year.
- 100,000 API requests a month across 5 keys
- Up to 500 saved widgets on 25 licensed domains
- 25 Business Calendars
- Batch up to 50,000 rows a job
- Advanced widget analytics, including per-domain breakdowns
Checking your account…
Compare plans
Every number below is the limit the product actually enforces.
| Feature | Free | Pro | Business |
|---|---|---|---|
| Browser calculators | All of them, unlimited | All of them, unlimited | All of them, unlimited |
| API calls a monthCounted per account, not per key. | 500 | 10,000 | 100,000 |
| API keys | 1 | 1 | 5 |
| API request history | Not included | 30 days | 90 days |
| Branded widgetsThe free embed URL works on any page, with a Calcadian credit. | Unlimited | Unlimited | Unlimited |
| White-label widgets | Not included | Included | Included |
| Saved widgets | Not included | Up to 20 | Up to 500 |
| Licensed domains | Not included | 3 | 25 |
| Business Calendars | Not included | 5 | 25 |
| Batch rows a job | Not included | Up to 5,000 | Up to 50,000 |
| Calculation Reports | Not included | PDF, CSV and JSON | PDF, CSV and JSON |
| Widget analytics | Not included | Basic, per widget | Advanced, per widget and per domain |
| Central widget manager | Not included | Not included | Included |
| MCP Basic | Included | Included | Included |
What people use the paid plans for
Delivery and lead-time dates
A shop calls the API with an order date and its own working calendar, and shows a delivery date that already skips weekends and public holidays.
A calculator on a client site
An agency saves a white-label widget, licenses the client's domain, and drops one iframe into the page.
Contract and notice periods
A team runs a CSV of contract start dates through Batch and gets every notice deadline back in one file.
A record of how a date was reached
Finance attaches a Calculation Report to a case file so the inputs and rules behind a deadline are on record.
Billing and usage
Upgrading from Pro to Business
An upgrade takes effect as soon as the payment succeeds. Your billing interval stays the same.
Because you are part-way through a paid period, Stripe works out a prorated amount for the rest of it and charges that. You see the amount before you confirm.
Downgrading from Business to Pro
A downgrade takes effect at the end of your current paid period. You keep Business features until then.
Nothing you created is deleted. Anything above the Pro limits, such as extra calendars, widgets or licensed domains, becomes inactive rather than removed, and comes back if you move up again.
Switching between monthly and annual
An interval change takes effect at your next renewal. Until then you keep the plan and the price you are already paying.
Cancelling
You can cancel at any time from the billing portal in your account.
Cancellation takes effect at the end of the period you have already paid for. Paid access continues until that date, then the account moves to Free.
Your API keys, calendars, widgets and settings are not deleted when a subscription ends.
If a renewal payment fails
Stripe retries the payment and Calcadian keeps your paid features for a 7-day grace period.
If the payment is not recovered in that time, the account falls back to Free. Your data and configuration are preserved, and paid features switch back on when a payment succeeds.
- What counts as an API request?
- One request to any /api/v1 operation, successful or not, counts once against your monthly quota. The quota belongs to the account, so all of your API keys draw from the same pool.
- What happens when I run out of API requests?
- Further requests return a quota error until the quota resets at the start of the next calendar month, UTC. Widgets, the browser calculators and your saved configuration keep working.
- Do extra API keys give me more requests?
- No. Keys exist so you can separate environments or rotate credentials. Business includes five keys and they share the same monthly quota.
- Can I change plan part-way through a period?
- Yes. Moving up applies straight away with a prorated charge. Moving down applies at the end of the period you have already paid for.
- What happens to my widgets if I stop paying?
- They keep calculating. White-label reverts to the branded version, custom logos stop rendering, and licences above the Free allowance become inactive. Nothing is deleted.
- How do I get an invoice?
- Stripe emails a receipt for every payment, and every invoice is available in the billing portal linked from your account.
Cancelling
You can cancel at any time from the billing portal. Cancellation takes effect at the end of the period you have already paid for, and your calendars, widgets and keys are not deleted when a subscription ends.
Building against the API? The developer documentation covers authentication, every operation and the error model. The product manual covers calendars, widgets, batch and reports.