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 Calendars may contain estimated dates, source omissions or unpublished years.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 through licence recovery 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.

Three layers of refresh guarantees

1. Server entitlement

   Refunds revoke entitlement immediately at the payment authority. Server entitlement follows Paddle within the webhook delivery delay plus ≤ 60 seconds of KV propagation. A fresh verification reads Paddle directly with no cache.

2. Stored add-on state

   The owner’s stored state updates within 24 hours through the daily trigger, or immediately on Recalculate Holiday Formulas, which performs a fresh verification.

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 custom function is honoured for at most 6 hours.

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.