[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"extension:v3:en:obb":3},{"resolvedFromAlias":4,"canonicalExt":5,"ext":5,"name":6,"category":7,"categoryName":8,"updatedAt":9,"popularity":10,"summary":11,"howToOs":12,"quickAnswer":18,"answerIntro":19,"whatIs":20,"description":21,"furtherReading":22,"openInstructions":38,"commonIssues":52,"securityNotes":71,"faq":75,"aliases":88,"mimeTypes":89,"relatedExtensions":90,"breadcrumbs":136,"categoryAnchor":146,"categoryFuturePath":147,"metaDescription":148,"availableHowToOs":149,"openOnDeviceLinks":150,"cannotOpenReasons":166,"cannotOpenFixes":167,"convertOptions":168,"securityAffiliateMessaging":169,"securityAffiliates":170},false,"obb","Android APK Expansion File (OBB)","archives","Archives","2026-06-12T08:42:09.008Z",55,".obb files are Android APK expansion files used to deliver large app assets (such as game data) outside the main APK. They are typically used by Android apps and the Android OS rather than opened directly by users.",[13,14,15,16,17],"windows","mac","linux","ios","android","To open .OBB files on Windows, if your goal is to use it with an Android app: connect your Android device to the PC and copy the .obb into /Android/obb/\u003Cpackage-name>/ on the device (create the folders if needed).","To “open” an .obb file, you normally place it in the correct /Android/obb/\u003Cpackage-name>/ folder so the associated Android app can use it. On a desktop, you can inspect it as a container with an archive tool, but the intended consumer is the Android app/OS.","An OBB is an “Opaque Binary Blob” used by Android as a container for additional application assets separate from the APK. Android provides APIs to mount and unmount OBBs (e.g., via StorageManager mountObb()/unmountObb()), and Google Play supports delivering them as APK expansion files with specific naming and location conventions.","Android apps—especially games—may need to ship large assets (maps, media, level data) that don’t fit comfortably inside the APK. For this use case, Android supports APK expansion files stored as .obb files, delivered alongside the APK and kept separate from the app package.",[23,26,29,32,35],{"title":24,"url":25},"APK Expansion Files (Android Developers)","https://developer.android.com/google/play/expansion-files.html",{"title":27,"url":28},"StorageManager API reference (Android Developers)","https://developer.android.com/reference/android/os/storage/StorageManager",{"title":30,"url":31},"JOBB tool documentation (Android Developers)","https://stuff.mit.edu/afs/sipb/project/android/docs/tools/help/jobb.html",{"title":33,"url":34},"OBB file overview (FileInfo)","https://fileinfo.com/extension/obb",{"title":36,"url":37},"Opaque binary blob (Wikipedia)","https://en.wikipedia.org/wiki/Opaque_binary_blob",{"windows":39,"macos":42,"linux":45,"ios":48,"android":50},[40,41],"If your goal is to use it with an Android app: connect your Android device to the PC and copy the .obb into /Android/obb/\u003Cpackage-name>/ on the device (create the folders if needed).","If your goal is to inspect contents: try opening the .obb with an archive tool (some OBBs can be viewed/extracted), but be aware the app may expect it unmodified.",[43,44],"To use with an Android app: transfer the .obb to the Android device and place it in /Android/obb/\u003Cpackage-name>/ with the expected name (for Play-style expansion files).","To inspect: try an archive utility to see if it can list or extract files; if it fails, treat it as an app-specific blob.",[46,47],"To use with an Android app: copy the .obb to the Android device into /Android/obb/\u003Cpackage-name>/ and ensure the file name matches what the app expects.","To inspect: try an archive tool to test whether it can read the container; many OBBs are meant to be mounted/used by Android rather than manually handled.",[49],"iOS apps do not use Android OBB expansion files; if you received an .obb, you’ll typically need to move it to an Android device or a desktop OS to do anything useful with it.",[51],"Install the associated app, then place the .obb under /Android/obb/\u003Cpackage-name>/ using a file manager (or let Google Play download it automatically); the app should detect and use it.",[53,59,65],{"title":54,"description":55,"steps":56},"App doesn’t detect the OBB file","Expansion files must be in the correct directory and typically follow a specific naming scheme (e.g., main/patch with version and package name). If the file is in the wrong folder or misnamed, the app won’t find it.",[57,58],"Verify the folder path is /Android/obb/\u003Cpackage-name>/ on the device storage and that the package name matches the app’s package identifier.","Check the file name follows the expected pattern (commonly [main|patch].\u003Cversion>.\u003Cpackage-name>.obb for Play expansion files), then relaunch the app.",{"title":60,"description":61,"steps":62},"Only a small .obb downloaded or it keeps re-downloading","Google Play manages expansion files; if the download is incomplete or the app expects a different version, it may repeatedly attempt to fetch the expansion file.",[63,64],"Confirm you’re using the correct app version that matches the expansion file version the app expects.","If using Play delivery, re-trigger the download through Google Play (or the developer’s testing process) rather than manually copying a mismatched file.",{"title":66,"description":67,"steps":68},"Can’t open/extract the .obb on desktop","Although some tools can treat OBBs like a container, OBB stands for “Opaque Binary Blob” and may not be a general-purpose archive format; some OBBs are intended to be mounted/consumed by Android APIs or the app itself.",[69,70],"Try an archive tool to list/extract; if it doesn’t recognize it, stop forcing extraction and use it as intended (placed on the Android device for the app).","Avoid modifying the file—many apps validate or assume a specific internal layout and may fail if contents change.",[72,73,74],".obb files are containers for app assets; treating them like archives and extracting unknown OBBs can expose you to malicious or malformed data that targets vulnerabilities in unpacking/parsing tools.","An OBB is tied to an app and package name/location conventions; downloading OBBs from unofficial sources can lead to tampered assets or mismatches that cause the app to crash or behave unexpectedly.","If you manually replace an app’s OBB, you are changing the data the app will load at runtime; only use OBBs obtained through trusted distribution (e.g., the app’s official delivery flow).",[76,79,82,85],{"question":77,"answer":78},"What is an .obb file used for on Android?","It’s an APK expansion file (an “Opaque Binary Blob”) used to store large additional assets for an Android app outside the APK, such as game data.",{"question":80,"answer":81},"Where should an .obb file go on the device?","For Play-style expansion files, they are stored under /Android/obb/\u003Cpackage-name>/ and commonly use a name like [main|patch].\u003Cversion>.\u003Cpackage-name>.obb.",{"question":83,"answer":84},"Can I open an .obb file like a ZIP?","Sometimes you can inspect it with an archive tool, but OBBs are designed as opaque containers for Android apps and may not be readable by general archive software.",{"question":86,"answer":87},"How do apps access OBB files?","Android provides APIs for working with OBBs (for example, StorageManager includes methods to mount and unmount OBB files), and the app reads assets from the mounted container.",[],[],[91,97,103,109,115,121,126,131],{"ext":92,"name":93,"category":7,"categoryName":8,"popularity":94,"summary":95,"howToOs":96},"zip","ZIP Archive",93,"ZIP archives are widely used to compress and bundle multiple files or folders for easier storage and sharing.",[13,14,15,16,17],{"ext":98,"name":99,"category":7,"categoryName":8,"popularity":100,"summary":101,"howToOs":102},"rar","RAR Archive",66,".rar files are compressed archive containers used to bundle and compress one or more files, often including split (multi-part) archives. They’re commonly opened by WinRAR and can usually be extracted by tools like 7-Zip and The Unarchiver.",[13,14,15,16,17],{"ext":104,"name":105,"category":7,"categoryName":8,"popularity":106,"summary":107,"howToOs":108},"bz2","bzip2 Compressed File",65,".bz2 is a bzip2-compressed file, typically used to shrink a single file for storage or download. To use the contents, you usually decompress it with an extractor such as 7-Zip or the bzip2 command-line tool.",[13,14,15,16,17],{"ext":110,"name":111,"category":7,"categoryName":8,"popularity":112,"summary":113,"howToOs":114},"7z","7-Zip Archive",64,"A .7z file is a 7-Zip compressed archive, commonly used to bundle and compress files with high compression ratios. Open it with 7-Zip on Windows or compatible archive tools such as WinRAR, Keka, The Unarchiver, p7zip, ZArchiver, or RAR.",[13,14,15,16,17],{"ext":116,"name":117,"category":7,"categoryName":8,"popularity":118,"summary":119,"howToOs":120},"gz","Gzip Compressed File",57,"GZ files are compressed using the gzip algorithm, commonly used for reducing file size and bundling files with TAR.",[13,14,15,16,17],{"ext":122,"name":123,"category":7,"categoryName":8,"popularity":10,"summary":124,"howToOs":125},"br","Brotli-compressed data",".br files contain data compressed with the Brotli algorithm, commonly used for web delivery. You open them by decompressing with Brotli tools or compatible archivers, then opening the extracted original file.",[13,14,15,16,17],{"ext":127,"name":128,"category":7,"categoryName":8,"popularity":10,"summary":129,"howToOs":130},"crx","Chrome/Chromium Extension Package (CRX)",".crx is the packaged format used to distribute Google Chrome and other Chromium-based browser extensions. It is essentially a signed wrapper around a ZIP archive containing the extension’s files.",[13,14,15,16,17],{"ext":132,"name":133,"category":7,"categoryName":8,"popularity":10,"summary":134,"howToOs":135},"ipa","iOS/iPadOS App Store Package (IPA)",".ipa is the package format for iOS/iPadOS apps. It is essentially a ZIP archive that contains an app bundle (typically under Payload/*.app) and related metadata used for installation and distribution.",[13,14,15,16,17],[137,140,143],{"label":138,"to":139},"Home","/",{"label":141,"to":142},"File Extension Index","/file-extension",{"label":144,"to":145},".OBB","/file-extension/obb","category-archives","/category/archives","Learn what .OBB files are, how to open them on every platform, common fixes, and security best practices.",[13,14,15,16,17],[151,154,157,160,163],{"os":13,"label":152,"to":153},"Open .OBB on Windows","/how-to/open-obb-on-windows",{"os":14,"label":155,"to":156},"Open .OBB on Mac","/how-to/open-obb-on-mac",{"os":15,"label":158,"to":159},"Open .OBB on Linux","/how-to/open-obb-on-linux",{"os":16,"label":161,"to":162},"Open .OBB on iOS","/how-to/open-obb-on-ios",{"os":17,"label":164,"to":165},"Open .OBB on Android","/how-to/open-obb-on-android",[54,60,66],[57,58],[],"archive",[171,175],{"name":172,"description":173,"affiliateUrl":174},"Avast","Avast offers free and premium antivirus software that protects against viruses, malware, ransomware, and phishing. Scan files before opening them to ensure safety.","https://www.avast.com/lp-aff-consumer-store?expid=inf601",{"name":176,"description":177,"affiliateUrl":178},"Norton","Norton 360 delivers comprehensive antivirus protection, VPN, and identity theft monitoring. Scan files for threats before opening to keep your device secure.","http://buy.norton.com/aff_home?utm_campaign=en-ww_nor_n36_aff_nas_nau_nah_cj_nad_low:_sec_nat_mktc_norton_360"]