MUHAMMADIYAH.OR.ID, YOGYAKARTA — The Muhammadiyah Council for Religious Opinion and Tajdid will conduct a national forum on the Unified Global Hijri Calendar in Yogyakarta on April 19–20. The forum marks an important step in preparing for the official use of the unified global Hijri calendar, set to begin on 1 Muharram 1447 AH.
This initiative is a follow-up to the 32nd Tarjih National Meeting held in Pekalongan in 2024 that Muhammadiyah scholars agreed to replace the wujudul hilal method with the Unified Global Hijri Calendar. The change was formalized in the Decree of the Central Board of Muhammadiyah No. 86/KEP/I.0/B/2025, demonstrating Muhammadiyah’s strong commitment to a unified Islamic calendar.
The national forum aims to build a shared understanding of KHGT across Muhammadiyah’s members. Realizing that such a major change may raise questions, the forum will offer space for dialogue and learning about both the religious reasoning and the technical calculations behind the calendar.
This forum is about aligning hearts and minds within Muhammadiyah, and even among the wider Muslims, so we can move forward together with a unified sense of time.
The forum will feature several speakers. Hamim Ilyas, Chairperson of the Muhammadiyah Council for Religious Opinion and Tajdid, will open with a talk on the official decisions that led to the Unified Global Hijri Calendar. Arwin Juli Rakhmadi Butar Butar will explain the religious principles behind the new way of determining Islamic months. Syamsul Anwar will discuss the use of global astronomical standards and how they fit within Islamic teachings, even when the crescent moon (hilal) is not visible above the horizon. Muhamad Rofiq Muzakkir will explore the global authority behind the Unified Global Hijri Calendar and how it can be accepted internationally. Oman Fathurohman will guide participants through the technical aspects of the Unified Global Hijri Calendar calculations to make sure everyone understands the process.
A highlight of the event will be the presentation of the Unified Global Hijri Calendar software, led by Tono Saksono and his team—Amirul Muslihin, Kasmui, Sriyatin Shodiq, and Ruswa Darsono. They will demonstrate how the software works and the criteria used to ensure its accuracy.
This forum is not just a technical discussion, but a moment of unity. Muhammadiyah hopes Unified Global Hijri Calendar will not only bring consistency in how Muslims observe the lunar calendar, but also strengthen the sense of togetherness and shared purpose across the global Muslim community.
