LibreOffice / OpenOffice (Windows, Mac, Linux)
If you need to convert a single ODT file to PDF, or in any case you don't have to transform a huge amount of documents at the same time, I strongly recommend that you contact LibreOffice o OpenOffice. On the other hand, it is with one of these two software that the files you need to convert have almost certainly been created!
The procedure you need to follow is very simple. After opening the ODT file to be transformed into PDF (by double clicking on its icon or selecting the item apri from the menu Fillet of OpenOffice / LibreOffice) and go to the menu File> Export to PDF format.
In the window that opens, make sure that in the field of Quality a value of at least 90% and that in the drop-down menu Reduce image resolution an option equal to or greater than is selected 300 DPI (otherwise the quality of the PDF will not be the best). Then he presses the button Export, select the folder in which to save the final document and click on Save but I will complete the operation.
If you want, you can also set a password to protect the PDF from unauthorized access (user password) or from changes and printing (owner password) by selecting the tab Safety e clicking on your button Set password.
CloudConvert (Online)
If you need to convert ODT to PDF in series, the simplest solution you can rely on is CloudConvert. In case you have never heard of it, this is an excellent online converter that allows you to convert many different file types together directly from the browser. It supports Office and OpenOffice documents, PDFs, images, videos, photos and more. It does not require registration and has no upload limits. Furthermore, it should be noted that it protects the privacy of users by deleting all the files that are uploaded to its servers within a few hours.
To use it, connected to its home page, click on the button Select files and select all the ODT documents to be transformed into PDF. Then press the button Start conversion, wait for the conversion process to finish and press the button Download that appears next to the name of the documents so that they can be downloaded to your computer.
You can also merge the content of multiple ODF files into a single PDF. How? selecting the item pdf from the menu merge all into one which is located at the bottom right and first pressing the button Start conversion and then Download.
Online2PDF (Online)
Another great online service that can help you transform OpenDocument files to PDF is Online2PDF which is as simple to use as CloudConvert, it allows you to merge multiple documents into one like the latter but has an upload limit: it does not allow you to upload more than 20 files simultaneously for a total weight of 100MB. As for privacy, do not worry, even in this case the files uploaded online are automatically deleted within a few hours.
To convert your documents with Online2PDF, linked to the home page of the service, drag them to the button Select files (or select them manually after pressing the same button) and choose from the drop-down menu fashion whether to convert ODT files separately (Convert files separately) or whether to combine them into a single PDF (Merge files).
So press the button Convert and within a few seconds the final PDFs will be automatically downloaded to your computer. Easier than that?
How to convert ODT to PDF