Sheet1Site collection storage limitUp to 1 TB per site collection. (25 GB for trial).List view threshold limit in site libraries and listsAfter 5000 items in a list or library, the list enters in reduced functionalitySite collections (#) per tenant500,000 site collections (other than personal sites).SubsitesUp to 2,000 subsites per site collectionPersonal site storageUp to 1 TB per user, as soon as provisioned.

Personal site storage applies to a users OneDrive for Business library and personal newsfeed. This amount is counted separately, and does not add to or subtract the overall storage allocation for a tenant.File upload limit2 GB per file.File attachment size limit250 MBDevelopment LimitsNo access to file/folder. It mean you can not use IO API commandsOnly be deployed at a site collection level scope (not farm scope)No access to web.configBlocked file types for SharePoint Online.ashx.asmx.json.soap.svc.xamlxDefault Timer JobsAre run daily and cannot be configuredAdditional timer jobsHave to be developedMapped Properties (for search)There is a limit of 200 mapped properties on SharePoint Online