International Ragnarok Online, or iRO, is an official Ragnarok Online service by American publisher Gravity Interactive Inc. on its WarpPortal brand. Since 2015, the service has been available to Philippine players, following the shutdown of Philippine Ragnarok Online (pRO). It is the longest-running official Ragnarok Online service.

iRO's Thor server was created in 2015 with migrated accounts from pRO.

iRO was launched on June 1, 2003, three months before the commercial launch of pRO in September 2003. From 2003 until 2015, Philippine players were forbidden to play on iRO as the license for the game was exclusively held by Level Up! Inc., the operator of the Level Up! brand in the Philippines.

On February 13, 2015, Level Up! announced that it would close the game on March 31, 2015. A migration program was held where pRO accounts would be migrated to iRO to a new server named "Thor". On March 31, 2015, the license for Ragnarok Online with Level Up! was terminated, and the Philippines was included as a service country of iRO.^{[doc 1]}

1. GRAVITY CO., LTD.'s Form 20-F for the fiscal year ended December 31, 2016