About Calcadian
Fast calendar math, without the clutter.
A focused hub of clutter-free date and time calculators for everyday planning.
Why we built Calcadian
Most date questions are small. How many days are left before a deadline? When will 30 working days have passed? What time is a meeting in another city? You should not have to build a spreadsheet to find out. Calcadian puts each calculation on a focused page, with a clear result and the rules behind it.
How the calculations work
Dates have a few details that are easy to miss. We explain the rules beside the calculators so you can check the answer before relying on it.
- Calendar days: The gap from January 1 to January 8 is 7 days. If a task counts both January 1 and January 8, that is 8 days. The Date Difference Calculator lets you choose.
- Working days: Saturdays and Sundays are normally excluded, and you can enter the holidays that matter to your schedule. Other weekend patterns and holiday rules depend on the tool or calendar you select. Try the Business Days Calculator.
- Months and leap years: A month is not a fixed number of days. Adding a calendar month is different from adding 30 days, especially near the end of February. Check both in the Add or Subtract Days Calculator.
- Weeks: ISO week numbers start on Monday. Week 1 includes January 4, so dates near New Year may belong to another ISO week-year. See the Week Number Calculator.
- Clock times: A local hour can shift across daylight saving time changes. The Time Zone Converter helps compare cities, while the Unix Timestamp Converter shows UTC alongside local time.
These are general calculation conventions, not rules for every contract or jurisdiction. If your deadline affects pay, taxes, healthcare or a legal obligation, check the governing document and local rules.
Privacy and accounts
The free on-page date and time calculators generally process the values you enter in your browser. You do not need an account to use those tools. Optional developer features, billing, reports and saved work may require a sign-in and use server-side services. We also use analytics with your consent. Read our privacy policy and cookie policy for details.
What to expect
- A calculator you can reach and use without creating an account.
- Clear descriptions, worked examples and direct links to related tools.
- Optional services for people who need more than a one-off calculation.
- Advertising may help support the free tools. We aim to keep it separate from inputs and results.
- No claim that a general calculator replaces a payroll, legal or statutory compliance system.
For calculation limits, see the disclaimer. If something looks wrong, please tell us what you entered and which result you expected. Do not send sensitive personal information.
Listed on SaaSHub
Calcadian is reviewed and approved on SaaSHub, a directory of software tools.
