CHM

Readable

other

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Identify it

Extensions	`.chm.chw`
MIME types	`application/vnd.ms-htmlhelp`
Signatures	`4954534603000000` at byte 0 (File Formats Wiki) `49545346` at byte 0 (Microsoft Compiled Help file)
PRONOM	`fmt/634`
Wikidata	`Q1023647`

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Open it

Apache TikaOpen sourcereads · Apache Software License 2.0
chmlibOpen sourcereads · GNU Lesser General Public License, version 2.1
ExifToolOpen sourcereads · Artistic License / GNU General Public License, version 1.0 or later
KCHMOpen sourcereads · GNU General Public License, version 2.0
libmspackOpen sourcereads · GNU Library General Public License, version 2.0
OkularOpen sourcereads · GNU General Public License, version 2.0
PhotoRecOpen sourcereads · GNU General Public License
Q215051Open sourcereads · GNU Lesser General Public License
Q479808Open sourcereads · GNU General Public License, version 3.0
xCHMOpen sourcereads · GNU General Public License
ZipegOpen sourcereads · BSD licenses
Adobe RoboHelpwrites
B1 Free Archiverreads · proprietary license
Chmoxreads
GnoCHMreads
ICE Book Readerreads
Q62853075reads

Convert it

No conversion recorded. One of the tools above may export it; search for a chain.

Sources

From Just Solve the File Format Problem (File Formats Wiki), PRONOM, Wikidata. Updated 2026-10-24.

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