Date Time Calc for Mac

Fast, reliable date and time calculations for professionals and power users. Add or subtract intervals, compare two dates, and get precise differences down to seconds—always formatted using your Mac’s locale and calendar settings.

Examples

• Add 150 days to today
• Difference in years, months, and days between 25 March 2009 and today
• Precise gap from last Monday 09:55:30 to next Friday 11:07:15
• Time from now to 10 December next year at 12:00 PM

Easy to use

• “Natural” inputs: years, months, days, weeks, hours, minutes, seconds
• Calendar Date mode (add/subtract Y/M/D)
• Time Precision mode (add/subtract days/hours/minutes/seconds)
• No Calculate button—results update instantly as you edit
• Clear textual summary under the fields
• One-click “Set to Now” for quick what-ifs
• Standard macOS date & time controls you already know

Features

• Live results as you type
• Differences shown with natural components (Y/M/D/W/H/M/S)
• Weeks supported for totals and differences
• Copy results as plain text
• Locale-aware date/time display and language
• Add or subtract intervals (past and future)
• Optional inclusion of hours, minutes, seconds for maximum precision
• Persistent log to keep your calculations across relaunches
• Reset the log at any time
• Built on Apple’s date/time frameworks for accuracy and calendar correctness
• Built-in PDF User Guide (Help menu)