7 free online tools in one place — calculate date differences, age, countdown timers, world clock, working days, week numbers, and time zones instantly.
CalcPlex's Time & Date Calculator Suite gives you seven precision tools — all free, all instant, and all in one page. Whether you need to find the number of days between two dates, calculate how many working days remain before a deadline, set a countdown timer to a birthday or event, or check the current time in multiple time zones, this suite handles it without any signup or installation.
All calculations run directly in your browser. No data is sent to any server, which means your dates stay completely private.
Here is a quick overview of all seven calculators included in this suite and what you can use them for:
Enter any date of birth to find the exact age in years, months, weeks, days, hours, and seconds. Great for verifying age for legal, medical, or birthday purposes. Supports any historical date.
Find the exact number of days between two dates — with breakdowns into years, months, weeks, and days. Toggle weekends on or off to calculate business days only.
Pick any future or past date and instantly see how many days remain until (or since) that date. Perfect for project deadlines, upcoming holidays, and events.
View the current time in major cities worldwide — New York, London, Dubai, Tokyo, Sydney, and more. Instantly convert between time zones for scheduling international meetings.
Calculate the number of business days between two dates, excluding weekends. Essential for project planning, HR leave management, and contract deadline tracking.
Find the ISO week number for any date, along with the day of the year, quarter, and a visual weekly calendar strip. Supports reverse lookup: enter a week number to find its dates.
Set a countdown to any date and time — birthdays, exam dates, product launches, New Year's. The timer displays days, hours, minutes, and seconds live and shows a real-time progress bar.
This suite is designed for anyone who regularly works with dates and time. Common use cases include:
Calculating the exact number of days between two dates is simple with CalcPlex:
Step 1: Click the Date Diff tab at the top of the calculator.
Step 2: Enter your Start Date in the first field.
Step 3: Enter your End Date in the second field.
Step 4: Click Calculate Difference. You will immediately see the result in days, weeks, months, and years.
Toggle the "Exclude Weekends" option if you only want to count weekdays (Monday–Friday). This is useful for calculating business days or working days between two dates.
Use the Date Diff tab on this page. Enter a start date and an end date, then click Calculate Difference. You will instantly see the total number of days, as well as the equivalent in weeks, months, and years. You can also toggle weekends off to count only business days.
Open the Age Calculator tab, enter your date of birth, and click Calculate Age. The tool will show your exact age in years, months, weeks, days, hours, minutes, and even seconds — updated to the present moment.
Click the Week No. tab, then enter or select the date you want to look up. The calculator will show the ISO week number, the day of the year, the quarter (Q1–Q4), the day of the week, and a visual calendar strip showing the full week.
Yes. The Work Days tab is dedicated to business-day calculations. Enter a start date and end date, and the calculator counts only Monday–Friday, skipping weekends automatically. This is ideal for calculating project durations, notice periods, or delivery windows.
Yes, completely free — no signup, no subscription, no ads. All seven tools (Age Calculator, Date Difference, Days Until, World Clock, Working Days, Week Number, and Countdown Timer) are available immediately with no restrictions.
Open the Timezones tab. It displays the current time across major cities worldwide — including New York (EST), London (GMT), Dubai (GST), Tokyo (JST), and Sydney (AEDT) — all updated in real time. Use it to coordinate calls or meetings across different time zones.
All calculations on this page use JavaScript's built-in Date object and ISO 8601 date arithmetic, which means results are accurate to the millisecond. Date difference calculations correctly account for leap years, and the world clock uses your browser's system timezone data (via the Intl.DateTimeFormat API) to ensure accurate time zone offsets.
Week numbers follow the ISO 8601 standard, which defines week 1 as the week containing the first Thursday of January. This is the standard used across most of Europe and in international business.
Looking for other types of calculators? CalcPlex offers 50+ free tools across multiple categories: