{"id":14523,"date":"2026-09-24T10:32:01","date_gmt":"2026-09-24T10:32:01","guid":{"rendered":"https:\/\/playgama.com\/blog\/?p=14523"},"modified":"2026-09-24T10:32:01","modified_gmt":"2026-09-24T10:32:01","slug":"when-should-a-browser-game-use-indexeddb-instead-of-localsto","status":"publish","type":"post","link":"https:\/\/playgama.com\/blog\/business-faqs\/when-should-a-browser-game-use-indexeddb-instead-of-localsto\/","title":{"rendered":"When should a browser game use IndexedDB instead of localStorage?"},"content":{"rendered":"

Use localStorage for small synchronous flags (settings, a single save slug) under a few hundred KB. Switch to IndexedDB when you store larger structured data, binary assets, many records, or need async, non-blocking reads and writes – for example level data, asset caches or multiple save slots.<\/strong><\/p>\n

At a glance<\/h2>\n\n\n\n\n\n\n\n
Fact<\/th>\nValue<\/th>\nSource<\/th>\n<\/tr>\n<\/thead>\n
localStorage is synchronous and origin-scoped<\/td>\nblocks main thread<\/td>\ndeveloper.mozilla.org<\/a><\/td>\n<\/tr>\n
localStorage persists across browser restarts<\/td>\nsame-origin only<\/td>\ndeveloper.mozilla.org<\/a><\/td>\n<\/tr>\n
MDN warns against heavy operations on localStorage<\/td>\nlarge\/CPU-heavy data<\/td>\ndeveloper.mozilla.org<\/a><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Use localStorage for small, simple, synchronous data: a settings object, a single JSON save blob, feature flags. Switch to IndexedDB when the data is large, structured, binary, or needs async access that won’t stall rendering: level packs, multiple save slots, downloaded asset caches, replay logs. MDN notes that “developers should be cautious when performing operations on sessionStorage or localStorage that involve a significant amount of data or computationally intensive tasks”<\/a> – because every read and write is synchronous and can block the main thread, which shows up as dropped frames in a game loop. IndexedDB’s transactional, asynchronous API avoids that.<\/p>\n

For actual player progress (level state, currency, purchases), don’t manage either storage yourself. The Playgama Bridge Storage module<\/a> picks the best place to store data per platform, including cloud saves where available, so progress survives device changes without you writing IndexedDB or localStorage code directly.<\/p>\n

What this looks like in code<\/h2>\n