Ragnarok Online is a free-to-play fantasy MMORPG developed by South Korean developer GRAVITY Co., Ltd. for Microsoft Windows. It is loosely based on the Korean manhwa Ragnarok: Into the Abyss. It is the first game in the Ragnarok franchise and is best known in the Philippines as the first officially licensed published MMORPG in the country.

Except for the Japanese and Vietnam services, almost all of the active official services are handled by publishers that are subsidiaries of or are related to the game's developer, GRAVITY.

A play-to-earn variation of Ragnarok Online called Ragnarok Landverse was launched in 2023. The Ragnarok franchise has also released multiple spinoffs on the mobile platform.

The following services are/were marketed to the Philippine region.

International Ragnarok Online (iRO) is listed above, as accounts from Philippine Ragnarok Online were migrated to a new server in iRO in 2015.

• September 2003: Philippine Ragnarok Online (pRO) was launched commercially in the Philippines under Level Up!.
• March 31, 2015: pRO was shut down. Player accounts were migrated to International Ragnarok Online on a new server named Thor.
• June 20, 2017: A new Ragnarok Online service in the Philippines was published by Electronics Extreme Ltd. called RO Extreme. RO Extreme also published a separate MY/SG service.
• July 10, 2019: RO Extreme's Philippine service was merged with the Malaysian/Singaporean service. The merged service was named Ragnarok Online MSP.
• November 28, 2021: RO MSP was shut down.
• February 23, 2022: A new service for the Philippines, Malaysia, and Singapore was launched by Gravity Game Hub. The service is named Ragnarok Online GGH.