MMDB file format description

Many people often share .mmdb files without providing instructions on how to use them. This can make it difficult for users to determine which program is compatible for editing, converting, or printing .mmdb files. To address this issue, we have created this page to offer assistance and guidance on handling .mmdb files. We provide information on compatible software, editing instructions and conversion options to help users effectively interact with .mmdb files.

Our aim is to simplify the process and promote seamless use of the .mmdb file format.

2 filename extension(s) found in our database.

.mmdb - Molecular Modeling Database

The MMDB data files are related to NCBI Toolkit. The MMDB file is a Molecular Modeling Database. The Molecular Modeling Database (MMDB) is a database of experimentally determined 3D-dimensional biomolecular structures and hosted by the National Center for Biotechnology Information (NCBI).

Application:NCBI Toolkit
Category:Data files
Magic:- / -

Molecular Modeling Database related extensions:

  • scw SQL Compare Data
  • sdd BPM Studio Editor Peak Data
  • dfm Midas ViewPoint Display Form
  • csc STK Calculation Scalar File
  • ml1 MultiLedger Balance Data
  • pjl ProCite Term and Journal Title List Data

.mmdb - MaxMind GeoIP2 Database

The MMDB data files are related to MaxMind GeoIP2. The MMDB file is a MaxMind GeoIP2 Database. MaxMind GeoIP2 is a library that enables the user to find geographical and network information of an IP address.

Application:MaxMind GeoIP2
Category:Data files
Magic:- / -

MaxMind GeoIP2 Database related extensions:

  • len Esko PlatePrep Len File
  • ldp Lingoes Dictionary Data
  • sfap0 Sound Forge Audio Proxy
  • hdl Giza Specifier HDL Data
  • fde AFP Form Definition
  • sy0 WordExpress Data

Be careful.

It is important to understand that the .mmdb file extension is not limited to a particular set of applications. Other programs besides the intended ones can also use the .mmdb extension to create files. This includes potentially harmful programs or malware that may generate .mmdb files for various purposes. Be especially cautious with .mmdb files coming from untrusted or unknown sources.

Can't open a .mmdb file?

When you double-click a file to open it, Windows examines the filename extension. If Windows recognizes the filename extension, it opens the file in the program that is associated with that filename extension. When Windows does not recognize an extension, you receive the following message:

Select an app to open this .mmdb file

To set the .mmdb file association in Windows 11, you can follow these steps

  1. Open the Settings app by clicking on the Start menu and selecting the gear icon.
  2. In the Settings app, click on System and then select Apps from the left-hand side menu.
  3. Scroll down and click on the Default apps option.
  4. Under the Default apps section, you will find various categories such as Email, Web browser, and Music player.
  5. Locate the category that matches the file type you want to associate, such as Photos for image files or Video player for video files.
  6. Click on the current default app listed under the category. A list of available apps will appear.
  7. Choose the app you want to set as the default for that file type. If the desired app is not listed, click on More apps to see additional options or click on Look for an app in the Microsoft Store to search for apps in the Store.
  8. After selecting the app, it will become the default choice for opening files of that type.

It's worth mentioning that you don't always need to set .mmdb file association. Many applications can open .mmdb files without requiring any specific file association to be set.

The .mmdb file extension is often given incorrectly

Based on searches conducted on our site in the past year, we have compiled a list of the most common misspellings. These frequent misspellings can cause confusion and hinder search accuracy. Our goal in providing this list is to help users find the right information more easily and enhance their overall search experience on our website.

These misspellings were the most common in the past year:

mdb, mmb, mmd, nmdb

Is it possible that the filename extension is misspelled?

There is a possibility that the .mmdb filename extension is misspelled. To assist users in identifying potential errors, we provide a list of similar file extensions in our database.

Filename extensions similar to .mmdb:

Operating systems

At, we strive to provide a seamless user experience by ensuring compatibility with a wide range of operating systems. The following is a comprehensive list of the operating systems currently supported by

Windows XP/Vista, Windows 7/8/10, Windows 11, CentOS, Debian GNU/Linux, Ubuntu Linux, FreeBSD, macOS, Mac OS X, iOS, Android

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If you find the information on this .mmdb page useful, please feel free to link to this page. >> MMDB file