Terms of service

Service and data coverage

Free: every formula for the current calendar year and the next one, in the spreadsheet’s timezone; country-level only, no subdivisions and no custom extra ranges. In 2026, that window is 2026–2027.

Pro: $29/year or $4/month; holiday lists: 2000–2035, subject to source coverage; business-day formulas: years with published calendars. Includes subdivisions, custom extra ranges, and priority data corrections. Compare plans and owner-based access.

Calendar data is derived from python-holidays under the MIT licence. Calendars may contain estimated dates, source omissions or unpublished years. Business-day formulas refuse incomplete calendars; holiday lists can still show known dates. Confirm critical schedules against the relevant published calendar and your organisation’s working rules. See data coverage.

2 seats, tied to spreadsheet owners

One Pro subscription includes 2 seats for two independent Google accounts, such as work and household accounts. Activate one seat in each spreadsheet owner’s account. A third activation is refused until a seat is released. Deactivate in the add-on’s sidebar releases that account’s seat; if you no longer have access to the account, licence recovery releases one using the Paddle receipt’s transaction ID.

• A Pro owner gives every editor Pro results in that spreadsheet.
• A Pro editor in a Free owner’s spreadsheet gets Free results. Ask the owner to activate, or make a copy owned by the Pro account.
• A copied spreadsheet uses its new owner’s tier.

Subscription and payment

Paddle is the merchant of record and handles purchase payments, recurring billing and receipts. Pro costs $29/year or $4/month for the chosen recurring billing interval. The checkout will show the total and any applicable tax before purchase.

Cancel through the subscription-management link provided with your Paddle purchase. Cancellation, a paused subscription, or a failed renewal preserves Pro only through the latest paid-through date. There is no advance coverage for an unpaid renewal. An approved refund removes the associated entitlement. The 14-day refund policy applies.

How fast a change reaches your cells

1. Server entitlement

   A refund revokes entitlement at the payment authority immediately. Our licence service follows Paddle within the webhook delivery delay plus up to a minute of cache propagation. A fresh verification reads Paddle directly with no cache. If a webhook is never delivered at all, the service re-reads Paddle within 6 hours and revokes then.

2. Stored add-on state

   The owner’s stored state refreshes once a day through a trigger installed at activation, and immediately on Recalculate Holiday Formulas, which performs a fresh verification. Google schedules the daily run inside a chosen hour, so consecutive runs sit around 24 hours apart rather than exactly.

3. Displayed cells

   Displayed cells change only when they execute again: on argument change, on Recalculate, or when Sheets re-executes them. A positive verification cached by a formula is honoured for at most 6 hours, and a negative one for at most 5 minutes — so a renewal restores Pro within 5 minutes, even in a spreadsheet whose owner has it closed.

4. The worst case, stated plainly

   Those layers stack, and the daily refresh is the slow one. A refund reaches our service within about a minute, but the spreadsheet’s stored state only changes when the daily refresh runs, so a cell that is not recalculated in the meantime can keep showing Pro for up to about a day. Recalculate Holiday Formulas ends that immediately. We would rather publish the real number than imply it does not exist.

These rules also apply to subscription expiry and the Free-window rollover on 1 January. Previously calculated values can remain visible until re-execution; the sidebar shows a rollover banner when opened.

Use and execution limits

There is no product cap on evaluations. Google’s Apps Script quotas, per-user execution limits and custom-function runtime limit still apply. Keep your licence key and Paddle transaction ID private. Share spreadsheet results through the owner-based model; do not distribute account activation credentials.

Changes and support

Calendar corrections are delivered through versioned data releases. Recalculate Holiday Formulas refreshes the index, re-verifies the licence, and rewrites Holiday Formulas cells so Sheets executes them again. A static holiday table remains a snapshot.

For billing, data or account issues, see support. This preparation copy must be checked together with the implementation and completed provider details before launch.