About WeekCalc.com

Our Mission

At WeekCalc.com, our mission is simple yet powerful: to provide accurate, fast, and completely free date and time calculation tools that anyone can use, anywhere, anytime. We believe that essential productivity tools shouldn't be locked behind paywalls, complex software installations, or intrusive registration processes. Everyone—from project managers coordinating international teams to students planning study schedules—deserves access to reliable date calculators that respect their privacy and time.

In an era where most "free" tools come with hidden costs (mandatory registrations, premium tiers, or privacy invasions), WeekCalc stands apart. We built our calculators with a privacy-first architecture that performs all calculations directly in your browser. This isn't just a feature—it's a fundamental commitment to your right to use productivity tools without surveillance or data collection.

What We Offer

WeekCalc.com provides a comprehensive suite of five specialized date and time calculators, each designed to solve specific professional and personal planning challenges:

Week Number Calculator

Our Week Number Calculator follows the ISO 8601 international standard, ensuring your week numbers align with European business practices, international project management systems, and global manufacturing schedules. Whether you're coordinating Agile sprints, planning production schedules, or simply communicating with international colleagues, our calculator provides the consistency and accuracy you need.

Days Between Dates Calculator

The Days Between Dates Calculator answers the fundamental question: "How much time exists between these two dates?" We provide results in multiple formats—days, weeks, months, and human-readable duration—because different contexts require different perspectives. Project managers, HR professionals, contract administrators, and event planners all rely on precise date difference calculations, and we deliver results they can trust.

Add/Subtract Days Calculator

When you need to know "What date will it be 90 days from now?" or "What was the date 45 days ago?", our Add/Subtract Days Calculator provides instant answers. From calculating Net 30 payment terms to determining project milestone dates, this tool handles the calendar arithmetic that would otherwise require mental math prone to errors, especially across month and year boundaries.

Workday Calculator

The Workday Calculator addresses a critical gap in date planning: the difference between calendar days and business days. By automatically excluding weekends, our calculator ensures your project timelines, SLA commitments, and delivery estimates reflect the reality of Monday-Friday work schedules. This simple distinction prevents the common planning errors that occur when calendar days and work days are confused.

Birthday Calculator

Our Birthday Calculator serves both practical and personal purposes. Whether you need exact age for HR records and benefits administration, or you're curious about how many days you've been alive and what day of the week you were born, this calculator provides comprehensive age information in a single, private calculation.

Why We're Different

Truly Free, Forever

When we say "free," we mean it. All five calculators are available with no limitations, no premium tiers, no trial periods, and no credit card requests. You can perform unlimited calculations without creating an account or providing any personal information. We support the service through ethical advertising (Google AdSense) while keeping all functionality completely free for all users.

Privacy by Design

Your dates are your business. We built WeekCalc with a client-side architecture where all calculations happen in your web browser using vanilla JavaScript. When you enter a birth date, project deadline, or any other date into our calculators, that information never travels to our servers. We can't see your data because we architected the system to make that technically impossible. This isn't just a privacy policy promise—it's built into the fundamental technology. Learn more in our Privacy Policy.

No Registration Required

We respect your time. You can arrive at WeekCalc, perform your calculation, and leave—all within seconds, with no account creation, email verification, or password management. While some services use mandatory registration to build user databases for marketing, we believe essential tools should be immediately accessible to everyone.

Mobile-First Design

Professionals work everywhere—at desks, in meetings, on job sites, and while traveling. Our calculators are built with responsive, mobile-first design that works flawlessly on smartphones, tablets, and desktop computers. Whether you're on a large office monitor or a small phone screen, the calculators remain fast, functional, and easy to use.

Lightning-Fast Performance

We built WeekCalc with vanilla JavaScript and zero external dependencies. No jQuery. No Bootstrap. No bloated frameworks that slow down page loads. This minimalist approach delivers sub-2-second load times even on slow connections and produces instant calculation results with no server round-trips. Fast performance isn't a luxury—it's a baseline requirement for productivity tools.

Standards-Compliant and Accurate

Our calculators follow international standards like ISO 8601 for week numbering, ensuring consistency with global business practices. We automatically handle leap years, varying month lengths, and year transitions. While we recommend verifying critical legal or financial calculations with appropriate professionals, our algorithms are thoroughly tested and reliable for planning and informational purposes.

Who We Serve

WeekCalc.com serves a diverse community of users who need reliable date calculations:

Project Managers use our calculators to build realistic timelines, calculate milestone dates, and communicate schedules clearly with stakeholders and international teams.

HR Professionals rely on our tools for benefits eligibility calculations, employment duration tracking, leave accrual management, and probation period determinations.

Students and Educators utilize our calculators to plan study schedules, calculate days until exams, manage assignment deadlines, and track academic timelines.

Small Business Owners depend on our tools for invoice payment term calculations (Net 30/60/90), delivery scheduling, follow-up planning, and vendor coordination.

Legal and Compliance Professionals use our calculators for preliminary date calculations related to filing deadlines, contract terms, and compliance periods (always verified with official systems for critical applications).

Anyone Planning Events benefits from our calculators when counting down to vacations, planning milestone celebrations, or organizing any event requiring precise date awareness.

Our Commitment to Quality

We're committed to maintaining WeekCalc as a reliable, trustworthy resource. This means:

• Accuracy: Regular testing ensures our calculations remain correct and handle edge cases properly.
• Uptime: Reliable hosting and simple architecture minimize downtime and ensure availability when you need it.
• Accessibility: Clean design, clear labels, and logical navigation make our tools usable for everyone, regardless of technical expertise.
• Transparency: Clear disclaimers, honest limitations, and straightforward policies ensure you know exactly what to expect.
• Continuous Improvement: We listen to user feedback and continuously refine our calculators to better serve your needs.

Looking Forward

While we're proud of our current calculator suite, we're always exploring ways to expand and improve. Future enhancements may include customizable holiday calendars for the Workday Calculator, additional date formats, downloadable calculation results, and new calculators based on user requests and needs. Our development roadmap is guided by one principle: making date and time calculations easier, faster, and more accessible for everyone.

Get in Touch

We value your feedback, questions, and suggestions. If you've found WeekCalc helpful, if you've encountered an issue, or if you have ideas for improvements, we want to hear from you. Visit our Contact Us page to get in touch. Your input helps us build better tools for everyone.

Thank You

Thank you for choosing WeekCalc.com for your date and time calculation needs. Whether you're here to plan a project, calculate an invoice due date, find your age in days, or simply satisfy curiosity about time, we're honored to be part of your workflow. We built these tools to be genuinely useful, truly free, and completely respectful of your privacy. We hope they make your planning a little easier and your time a little more productive.

— The WeekCalc Team