Libera.Date.Api is a high-precision date calculation engine designed to streamline business logic for global applications. Its core strength lies in its advanced Working Days System, which accurately calculates business days by automatically excluding weekends and public holidays for multiple countries (including 100 countries). Beyond simple duration checks, the API offers intelligent scheduling tools like finding the nearest available working day, analyzing date ranges for non-working intervals, and distinguishing between standard weekends and legal holidays. Whether you are computing SLAs, planning delivery windows, or building HR rosters, Libera.Date.Api ensures your dates align with real-world business calendars.

Count working days between two dates or add business days to a date, skipping weekends and public holidays of 100+ countries and regions.

Accurate business-day, holiday, and scheduling math for major countries and their subdivisions — without maintaining a single holiday calendar yourself. Add or subtract working days, check if a date is a business day, find the next valid date, or count working days between two dates, with full support for regional subdivisions, custom weekends, and your own blackout dates. One simple GET call, instant JSON.

Enhance your scheduling with the Smart API, designed to simplify date and business day calculations with intelligence.

Trust our Reliable API for consistent date and business day calculations, ensuring you never miss a deadline again.

The Global API delivers seamless date and business day calculations worldwide, catering to international business needs.

Get precise results every time with our Accurate API for calculating dates and business days—perfect for business professionals.

Look up public holidays for 55 countries, calculate business day deadlines, find the next business day, export holidays to iCal, and more — all backed by versioned JSON data with no external dependencies at runtime. Covers 55 countries across Africa, Americas, Asia, Europe and Oceania for years 2024 to 2027.

Check and retrieve holiday data from around the world with ease and accuracy.

Pregnancy due date and gestational age API. EDD from LMP, conception, IVF transfer day, or ultrasound CRL. ACOG redating rules, trimester, and term milestones. Deterministic ISO 8601 dates.

Calculates business days, SLA due dates, holiday-aware deadlines, skipped weekends and holidays, business hours, and business-time durations.

Calculate payroll costs in different markets to streamline budgeting and human resources.

Explore notice period requirements across 40 countries for seamless workforce transitions.

Gestational age at any given date, returned as a 29w2d label and as total days.

Ovulation estimate and 6-day fertile window from cycle length. Not contraceptive guidance.

Antenatal visit dates from the WHO 2016, NICE or ACOG published schedules, as calendar dates.

Due date from embryo transfer date. Day-3, day-5, day-6 and egg retrieval calculated separately.

Applies ACOG Committee Opinion 700 Table 1 to decide whether an ultrasound overrides LMP dating.

Due date from last menstrual period using Naegele's rule, with 21-45 day cycle length correction.

Trimester boundaries, 24w0d viability, and four preterm and four term classes with their dates.

Dating from BPD, HC, AC and FL measurements in millimetres, using Hadlock 1984 equations.

Conception date from a last menstrual period or from a known due date, as ISO 8601 dates

Learn about 13th month pay regulations to ensure compliance and attract talent globally.

Calculate business days accurately while accessing global holiday data to optimize your workflows.

Ensure timely project deliveries with the SLA Deadline Calculator, using global holidays for precise deadline calculations.