If you are into teaching the IPA to your students, you are not alone. Some English teaching professionals are convinced that getting your students acquainted with the IPA works for them to become a little bit more autonomous. Check this ELT author for more on this theory.
Now, suppose you decide to practice the IPA in class and you want to change a text into IPA for your students to get the hang of it. You find your words in an online dictionary and copy the IPA transcription for each of them, or you could use a reliable online IPA transcription tool than can save you a lot of time. A transcription tool allows you to turn words or small chunks of sentences into IPA code.
Here are some reliable transcription tools that you can find online. Give them a try.