Top 10 CHM Book Readers
Updated: March 10, 2026 | Editor: Maria Lin
These reading apps allow to open and read CHM books. CHM format was created by Microsoft for help files, but became useful for ebooks also. It consists of a collection of HTML pages, an index and other navigation tools. CHM files open on any Windows computer without additional software. There are also reading apps for Mac, Linux, Android and iOS that support CHM books. You can also find some free cloud tools that allow to open CHM online.
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Free e-book reader that supports multiple file formats, including ePub, fb2, mobi, HTML, RTF, HTML, plain text, doc, and more. FBReader uses its own page parsing and rendering engine - very lightweight, fast and customizable. It supports embedded images, footnotes, hyperlinks, text search, full-screen reading. It also automatically creates bookmarks so you don't lose track of where you left off after closing a book. It works on iOS, Android, Windows, Mac OS, Linux, and Chrome OS. Books can be synced across devices or stored in Google Drive. For Android and iOS there are both free and paid versions. Free versions have some limitations.
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AlfaReader is a lightweight and fast ebook reader, ideal for reading electronic magazines, student textbooks, medical, scientific, technical books, illustrated books for kids. Allows to make bookmarks, save knowledge blocks, add comments, download books for OPDS. Includes built-in audiobook player. Integrates with popular ebook organizer Alfa Ebooks Manager.
3
Popular Android app that lets read books offline or directly from online book sites and OPDS. It features a comfortable viewing mode with smooth scrolling, full set of visual settings: line spacing, font size, bold, italic, shadow, alpha channel, smooth edge transitions. Over 10 built-in themes, including a day/night mode switch. Various page navigation options: touchscreen, volume keys, even the camera, search, or back buttons. The free version is ad-supported, while the paid version offers TTS engine, PDF support, more beautiful backgrounds, fonts and reading themes, password protection on startup, annotation sharing, reading statistics.
4
Free open-source, XML/CSS-based e-book reader for Windows and Linux. There's also mobile version for Android and some eInk devices. Supported formats include FB2, TXT, RTF, DOC, TCR, HTML, EPUB, CHM, PDB, and MOBI. The program offers numerous settings for improved reading experience. It's arguably the best reader for Linux, but on Windows, it has some issues, such as linking e-book extensions to the program so it opens when clicking on a book file.
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SumatraPDF, also known as Sumatra, is a free and open-source software PDF reader for Microsoft Windows only. The program also opens Open XML Paper Specification, DjVu, EPUB, XPS, CHM, CBZ and CBR, and MOBI files
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KOReader is a document viewer for E Ink devices. Supported file formats include EPUB, PDF, DjVu, XPS, CBT, CBZ, FB2, PDB, TXT, HTML, RTF, CHM, DOC, MOBI and ZIP files. It’s available for Kindle, Kobo, PocketBook, Android and desktop Linux.
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Multi-functional Android app for reading books. It features automatic folder scanning and adding books to the library, bookmarks, annotations, TOC, online catalog and dictionary support, syncing between Android devices via Google Drive (reading progress, bookmarks, etc.), day and night modes, custom CSS support, "Musician mode" with adjustable scrolling speed, TTS reading, built-in media player and online format conversion. The volume control functionality, background and fonts can be customized. All collections can be viewed in a list or grid view. Books are easily identified by thumbnail covers with adjustable size and style, as well as detailed descriptions. The free version contains ads.
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Not only an eBooks, Comics reader but also a tons-of-free-ebook-downloader, with dictionary inside for you to studies languages.
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ReadEra is an Android application for reading books and viewing documents, free and without ads. Open and read book files in EPUB, FB2, PDF, DJVU, MOBI, DOC, RTF, TXT and CHM formats. Automatically detects and displays the list of all supported documents on your device, Identifies duplicate files. Support for a table of contents, bookmarks, visual styles. Automatically saves the current reading position, even if the files are moved or temporarily deleted.
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Okular is a universal book viewer based on KPDF for KDE 4. This means Okular works on multiple platforms, including but not limited to Linux, Windows, Mac OS X, *BSD, etc. Okular combines the excellent functionalities of KPDF with the versatility of supporting different kind of documents, like PDF, Postscript, DjVu, CHM, XPS, ePub and others.
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A light weight yet powerful CHM file reader. Auto scan CHM file in SDCard, or you can select the book folder. TOC tree support. Full screen support. Auto set zoom level and page scoll of your last reading. Large file support. Bookmarks. Language encoding. Brightness adjustment. Night mode.
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iPhone app for reading books in CHM format. It lets you organize your books into personal collections, add bookmarks or notes to your favorite passages, find the text you need anywhere in the book. The app features customizable fonts for headings, body text, and code snippets, adjustable line height, fast scrolling, and seamless page navigation. You can share quotes with friends on Facebook, X, or by email, find a words, characters or phrases anywhere in the book using the built-in search function, add files from your computer browser or iTunes file sharing. The paid version allows to read multiple books simultaneously.
