What Is a File Extension and MIME Type?

A reference to help you identify MIME types and file extensions

A multipurpose internet mail extension, or MIME type, is an internet standard that describes the contents of internet files based on their natures and formats. This cataloging helps the browser open the file with the appropriate extension or plugin. Although the term includes the word "mail" for electronic mail, it's used for web pages, too.

Defining MIME Types

MIME types contain two parts: a type and a sub-type.

  • The type describes the categorization of MIME types linked to each other.
  • In contrast, a subtype is unique to a specific file type that is part of the type.

Here is the MIME type for HTML:

text/html

MIME types are defined in HTML by the type attribute on links, objects, and script and style tags.

A mime looking at a laptop with surprised look on his face
vladimir_karpenyuk / Getty Images 

Distinguishing Among MIME Types

Following is a list of most MIME types, their file extensions, and the applications that use them. Many computers use file extensions to identify file types. So, if you have a file with an odd extension on your website, you can look up the MIME type in this list.

Some types come with the X prefix, and some have the prefix VND. These prefixes, respectively, refer to sub-types not listed with the Internet Assigned Numbers Authority or values specific to a vendor.

MIME Types: Applications

Here's a broad list of MIME types by application and file extension.

Application MIME Type File Extension
Corel Envoy application/envoy evy
fractal image file application/fractals fif
Windows print spool file application/futuresplash spl
HTML application application/hta hta
Atari ST Program application/internet-property-stream acx
BinHex encoded file application/mac-binhex40 hqx
Word document application/msword doc
Word document template application/msword dot
Binary file application/octet-stream *
binary disk image application/octet-stream bin
Java class file application/octet-stream class
Disk Masher image application/octet-stream dms
executable file application/octet-stream exe
LHARC compressed archive application/octet-stream lha
LZH compressed file application/octet-stream lzh
CALS raster image application/oda oda
ActiveX script application/olescript axs
Acrobat file application/pdf pdf
Outlook profile file application/pics-rules prf
certificate request file application/pkcs10 p10
certificate revocation list file application/pkix-crl crl
Adobe Illustrator file application/postscript ai
postscript file application/postscript eps
postscript file application/postscript ps
rich text format file application/rtf rtf
set payment initiation application/set-payment-initiation setpay
set registration initiation application/set-registration-initiation setreg
Excel Add-in file application/vnd.ms-excel xla
Excel chart application/vnd.ms-excel xlc
Excel macro application/vnd.ms-excel xlm
Excel spreadsheet application/vnd.ms-excel xls
Excel template application/vnd.ms-excel xlt
Excel workspace application/vnd.ms-excel xlw
Outlook mail message application/vnd.ms-outlook msg
serialized certificate store file application/vnd.ms-pkicertstore sst
Windows catalog file application/vnd.ms-pkiseccat cat
stereolithography file application/vnd.ms-pkistl stl
PowerPoint template application/vnd.ms-powerpoint pot
PowerPoint slide show application/vnd.ms-powerpoint pps
PowerPoint presentation application/vnd.ms-powerpoint ppt
Microsoft Project file application/vnd.ms-project mpp
WordPerfect macro application/vnd.ms-works wcm
Microsoft Works database application/vnd.ms-works wdb
Microsoft Works spreadsheet application/vnd.ms-works wks
Microsoft Works word processor document application/vnd.ms-works wps
Windows help file application/winhlp hlp
binary CPIO archive application/x-bcpio bcpio
computable document format file application/x-cdf cdf
Unix compressed file application/x-compress z
gzipped tar file application/x-compressed tgz
Unix CPIO archive application/x-cpio cpio
Photoshop custom shapes file application/x-csh csh
Kodak RAW image file application/x-director dcr
Adobe Director movie application/x-director dir
Macromedia Director movie application/x-director dxr
device independent format file application/x-dvi dvi
Gnu tar archive application/x-gtar gtar
Gnu zipped archive application/x-gzip gz
hierarchical data format file application/x-hdf hdf
internet settings file application/x-internet-signup ins
IIS internet service provider settings application/x-internet-signup isp
ARC+ architectural file application/x-iphone iii
JavaScript file application/x-javascript js
LaTex document application/x-latex latex
Microsoft Access database application/x-msaccess mdb
Windows CardSpace file application/x-mscardfile crd
CrazyTalk clip file application/x-msclip clp
dynamic link library application/x-msdownload dll
Microsoft media viewer file application/x-msmediaview m13
Steuer2001 file application/x-msmediaview m14
multimedia viewer book source file application/x-msmediaview mvb
Windows meta file application/x-msmetafile wmf
Microsoft Money file application/x-msmoney mny
Microsoft Publisher file application/x-mspublisher pub
Turbo Tax tax schedule list application/x-msschedule scd
FTR media file application/x-msterminal trm
Microsoft Write file application/x-mswrite wri
computable document format file application/x-netcdf cdf
Mastercam numerical control file application/x-netcdf nc
MSX computers archive format application/x-perfmon pma
performance monitor counter file application/x-perfmon pmc
process monitor log file application/x-perfmon pml
Avid persistent media record file application/x-perfmon pmr
Pegasus Mail draft stored message application/x-perfmon pmw
personal information exchange file application/x-pkcs12 p12
PKCS #12 certificate file application/x-pkcs12 pfx
PKCS #7 certificate file application/x-pkcs7-certificates p7b
software publisher certificate file application/x-pkcs7-certificates spc
certificate request response file application/x-pkcs7-certreqresp p7r
PKCS #7 certificate file application/x-pkcs7-mime p7c
digitally encrypted message application/x-pkcs7-mime p7m
digitally signed email message application/x-pkcs7-signature p7s
Bash shell script application/x-sh sh
Unix shar archive application/x-shar shar
Flash file application/x-shockwave-flash swf
Stuffit archive file application/x-stuffit sit
system 5 release 4 CPIO file application/x-sv4cpio sv4cpio
system 5 release 4 CPIO checksum data application/x-sv4crc sv4crc
consolidated Unix file archive application/x-tar tar
Tcl script application/x-tcl tcl
LaTeX source document application/x-tex tex
LaTeX info document application/x-texinfo texi
LaTeX info document application/x-texinfo texinfo
unformatted manual page application/x-troff roff
Turing source code file application/x-troff t
TomeRaider 2 ebook file application/x-troff tr
Unix manual application/x-troff-man man
readme text file application/x-troff-me me
3ds Max script file application/x-troff-ms ms
uniform standard tape archive format file application/x-ustar ustar
source code application/x-wais-source src
internet security certificate application/x-x509-ca-cert cer
security certificate application/x-x509-ca-cert crt
DER certificate file application/x-x509-ca-cert der
public key security object application/ynd.ms-pkipko pko
zipped file application/zip zip

MIME Types: Sound Files

This list details common sound file MIME types by file extension and application.

Application MIME Type File Extension
audio file audio/basic au
sound file audio/basic snd
midi file audio/mid mid
media processing server studio audio/mid rmi
MP3 file audio/mpeg mp3
audio interchange file format audio/x-aiff aif
compressed audio interchange file audio/x-aiff aifc
audio interchange file format audio/x-aiff aiff
media playlist file audio/x-mpegurl m3u
Real Audio file audio/x-pn-realaudio ra
Real Audio metadata file audio/x-pn-realaudio ram
WAVE audio file audio/x-wav wav

MIME Types: Image Files

Image files also come in various MIME types by application.

Application MIME Type File Extension
Bitmap image/bmp bmp
compiled source code image/cis-cod cod
graphic interchange format image/gif gif
image file image/ief ief
JPEG image image/jpeg jpe
JPEG image image/jpeg jpeg
JPEG image image/jpeg jpg
JPEG file interchange format image/pipeg jfif
scalable vector graphic image/svg+xml svg
TIF image image/tiff tif
TIF image image/tiff tiff
Sun raster graphic image/x-cmu-raster ras
Corel metafile exchange image file image/x-cmx cmx
icon image/x-icon ico
portable any map image image/x-portable-anymap pnm
portable bitmap image image/x-portable-bitmap pbm
portable graymap image image/x-portable-graymap pgm
portable pixmap image image/x-portable-pixmap ppm
RGB bitmap image/x-rgb rgb
X11 bitmap image/x-xbitmap xbm
X11 pixmap image/x-xpixmap xpm
X-Windows dump image image/x-xwindowdump xwd

MIME Types: Mail Message Files

Mail message files come in these MIME types and file extensions.

Application MIME Type File Extension
MHTML web archive message/rfc822 mht
MIME HTML file message/rfc822 mhtml
Windows Live Mail newsgroup file message/rfc822 nws

MIME Types: Text Files

You might encounter text files in the following MIME types and with these familiar file extensions.

Application MIME Type File Extension
Cascading Style Sheet text/css css
H.323 internet telephony file text/h323 323
HTML file text/html htm
HTML file text/html html
Exchange streaming media file text/html stm
NetMeeting user location service file text/iuls uls
BASIC source code file text/plain bas
C/C++ source code file text/plain c
C/C++/Objective C header file text/plain h
text file text/plain txt
rich text file text/richtext rtx
Scitext continuous tone file text/scriptlet sct
tab separated values file text/tab-separated-values tsv
hypertext template file text/webviewhtml htt
HTML component file text/x-component htc
TeX font encoding file text/x-setext etx
vCard file text/x-vcard vcf

MIME Types: Video Files

This table lists video file MIME types and commonly used applications.

Application MIME Type File Extension
MPEG-2 audio file video/mpeg mp2
MPEG-2 audio file video/mpeg mpa
MPEG movie file video/mpeg mpe
MPEG movie file video/mpeg mpeg
MPEG movie file video/mpeg mpg
MPEG-2 video stream video/mpeg mpv2
MPEG-4 video/mp4 mp4
Apple QuickTime movie video/quicktime mov
Apple QuickTime movie video/quicktime qt
Logos library system file video/x-la-asf lsf
streaming media shortcut video/x-la-asf lsx
advanced systems format file video/x-ms-asf asf
ActionScript remote document video/x-ms-asf asr
Microsoft ASF redirector file video/x-ms-asf asx
audio video interleave file video/x-msvideo avi
Apple QuickTime movie video/x-sgi-movie movie

MIME Types: Virtual World Files

This list covers virtual world file MIME types by application.

Application MIME Type File Extension
Flare decompiled actionscript file x-world/x-vrml flr
VRML file x-world/x-vrml vrml
VRML world x-world/x-vrml wrl
compressed VRML world x-world/x-vrml wrz
3ds max XML animation file x-world/x-vrml xaf
Reality Lab 3D image file x-world/x-vrml xof
FAQ
  • How do browsers deal with unknown MIME data types?

    If a server reports an unknown MIME type, your browser won't be able to properly display the content. Some browsers will try to guess the MIME type, which can result in unexpected behavior. Other browsers will display unknown content as plain text or not at all.

  • What is S/MIME?

    S/MIME stands for Secure/Multipurpose Internet Mail Extensions. It's an encryption standard you can use to encrypt emails in Gmail and other email clients that support it. Enabling S/MIME allows you to digitally sign emails to verify that you are the legitimate sender of the message.

Was this page helpful?