Some tools to create, convert and verify EPUB

Home / Factorsim / Some tools to create, convert and verify EPUB

The EPUB format is an open and free available standard for eBooks publication. Given that the vast majority of eReaders available in the market recognises this format, its popularity has increased. In comparison with other formats such us PDF or DOC, its main advantage  is its capacity to adapt to different screens by resizing the text according to the user\’s needs. Besides, EPUB uses Unicode, so there will not be problems related to the recognition of graphic characters such as signs or symbols.

How do I create or edit an EPUB?

The most popular text editors do not include the option to export to this format yet, but there are programmes that make this task easier.

Factorsim recommends Sigil because it is powerful and easy to use as well as highly spread. This open software, free and multiplatform allows you to edit and create ebooks  following the concept WYSIWYG (What You See Is What You Get).


First thing we see when opening the program is an interface divided into four parts:

  • The top toolbar: very similar to that of any text editor.
  • Book browser: our EPUB menu, where there will appear the files that the package will contain when exporting it.
  • Book view: displays how the book we are creating will be shown in the eReader (code view can be activated, too).
  • Navigable table of contents

The text can be added from HTML files, from an EPUB file that we have previously or by writing directly in Sigil.

Sigil allows you to create all the necessary sections, right-click on the first section and on “add blank HTML file” in the menu.


The process for images is very similar; first of all, we locate them in the folder “Images” and then, in the section we want with the function “add file” of the menu bar.

It is very important that all the sections and images have an associated concept, i.e., a tag that identifies which kind of content appears in this space. Right-click on each item and choose the option “add concept”.


Create an index is a very simple task too, because the program offers the possibility to automate the process, provided that the headings of each chapter or other headings have been organized hierarchically by using different headings.


In order to finish, eBook metadata should be added by choosing among the multiple properties and validating that the creation does not contain any mistake before exporting the project.

How do you convert an EPUB or other formats?

Calibre is another application we should install if we are going to use electronic books.

It is a program to manage eBooks collections that has the option to convert into different formats. As well as Sigil, Calibre is open, free and multiplatform.


You are probably asking yourself why you need a converter if we have already exported our project to EPUB. Well, although EPUB is the most popular format, some devices such as Kindle from Amazon do not recognise it and you need to convert them into another format such as MOBI.

It is not only useful for these purposes, but it can also be used in order to transfer to EPUB PDF or TXT files that we already have and be edited with Sigil, therefore, if we start from content we had before, the process of creating an electronic book is faster. 

Calibre recognizes the following contents: EPUB, LRF, HTML, LIT, MOBI, TPZ, TXT, RTF, PDF, SNB, CBZ, CBR, CBC, ZIP, RAR, ODT, DOC, DOCX.

Calibre can convert the following formats: EPUB, MOBI, AZW3, FB2, HTMLZ, LIT, LRF, PDB, PDF, PMLZ, RB, RTF, SNB, TCR, TXT, TXTZ, ZIP.

How do I validate an EPUB?

The validation and test are very important steps in the creation of any project. The ebook should be created by a validator such as Epubcheck or that uses the same system and requires no installation.

This tool will indicate if there is any mistake in the file created and where it is. In case of mistakes, we should go back to Sigil, activate the code view and solve the problems indicated. The tool “search and substitute” can be really helpful in this case.

To sum up, it is convenient to test the book in different devices in order to make sure that everything works as it should before distributing or publishing it in various platforms.

Dejar un comentario


5 × 4 =


Puedes enviarnos un mensaje si tienes quejas o quieres felicitarnos, o para contarnos algo, te responderemos :D