The day began for many Sunni Arabs in Iraq with early morning services at their mosques to mark the start of the Eid al-Fitr holiday.
For Iraqi Shi'ites, however, Eid will begin tomorrow.
Little violence had been reported by midday in Iraq, after some 40 people were killed yesterday in several bomb attacks, including one outside a mosque.
The Muslim festival also started today in Afghanistan, Central Asia, and Russia.
In remarks today in Kabul, President Hamid Karzai said the suffering in Pakistan tempers the Eid celebrations:
"While congratulating all Afghan people on Eid yesterday,I heard that the earthquake in Pakistan has killed more than 73,000 people and many have lost their homes," Karzai said. "May God change their sadness into happiness. And with the grace of this holy day, may God bless them with a safe and better life in the coming winter."
In India, Eid will be celebrated either tomorrow or on 5 November amid tightened security following three bombings on 29 October in the capital, New Delhi. Fifty-nine people were killed.
(Compiled from agency reports)