What is the ACCDE file format?
.accde is a compiled, execute-only version of a Microsoft Access database file (.accdb). It is produced from an existing .accdb source file via Database Tools > Make ACCDE in Microsoft Access.
When Access compiles an .accdb to .accde, all Visual Basic for Applications (VBA) source code is permanently stripped; only the compiled p-code (bytecode) is retained. The resulting file runs forms, reports, and macros normally, but cannot be opened in Design view - table structures, form layouts, and report designs are locked for editing. This protects intellectual property in distributed database applications. The conversion is one-way: the original .accdb must be preserved separately, as there is no way to recover VBA source from an .accde.
.accde uses the ACE (Access Connectivity Engine) binary engine - the same format as .ACCDB - with 4096-byte pages and the Standard ACE DB file header. Both file types share identical magic bytes; the only binary difference is the absence of source-code streams in .accde.
Microsoft Access Runtime (a free download) can run .accde applications without a full Access license. .accde maps to the .accdb era (Access 2007 and later); the equivalent for older .mdb databases is .MDE.
Security & safety
RISK: MEDIUMAn ACCDE file can contain compiled VBA p-code and data macros that execute when the database is opened or forms are used. Because the source code is hidden, a malicious developer could distribute an ACCDE with hidden actions. Access opens ACCDE files with Trust Center restrictions; do not bypass security prompts for ACCDE from untrusted sources. The data itself is accessible (tables/queries) but code behavior cannot be audited without Access's macro tools. Optional encryption (AES-128 on Access 2010+) protects data at rest.
Format details
in a nutshellPrograms that open ACCDE files
Windows3 apps
Microsoft Access
Paid Double-click the .accde to run the application. Note: design view is disabled - you can use the forms/reports but not modify code or layouts. 
Microsoft Access Runtime
Free Free runtime that runs ACCDE applications on machines without a full Access license. Download and install, then open the .accde. No design or development capabilities.
Office 365 (Access component)
Paid Access is included in Microsoft 365 Business Standard and higher plans; same experience as standalone Access. Technical details
deep spec| Base format | ACE (Access Connectivity Engine) binary database - structurally identical to .accdb |
| Magic bytes | 00 01 00 00 at offset 0; 'Standard ACE DB' (53 74 61 6E 64 61 72 64 20 41 43 45 20 44 42) at offset 4 |
| Page size | 4096 bytes per database page (same as .accdb) |
| Byte order | Little-endian |
| VBA source code | Permanently stripped during Make ACCDE compilation - only compiled p-code (bytecode) retained; source is not recoverable |
| Design-view access | Disabled - forms, reports, and VBA modules cannot be viewed or modified by recipients |
| Encryption | Optional AES-128 database-level password protection (Access 2010+); weaker cipher in Access 2007 .accde |
| Creation method | Database Tools > Make ACCDE in Microsoft Access - a one-way, irreversible compilation process |
| Runtime deployment | Runs on free Microsoft Access Runtime without a full Access license |
| Companion lock file | .laccdb created when the database is open (same as .accdb) |
| Predecessor format | .mde - same execute-only concept for legacy .mdb / Jet engine databases (Access 97-2003) |
| Platform | Windows only (ACE engine has no macOS or cross-platform support) |
| MIME type | application/x-msaccess |
| Released | 2007 (Access 2007, as the ACCDB-era replacement for .mde) |
| Latest version | Compatible with Microsoft 365 Access (2024) |
| Specification | learn.microsoft.com |
ACCDE conversions
Community Q&A
asked by usersNo questions yet - be the first to ask about ACCDE files.
