The book Mastering ArduinoJson contains everything you need to learn how to use the library. Obviously, the book explains how to use the library, but that's not all. It also contains a short C++ course that teaches the crucial concepts that many Arduino developers lack. It demonstrates how to use the library in various projects through several case studies.

I wrote the book with the same care (if not more) than with the library. From the fantastic feedback, I even start to believe that this book is actually quite good. See by yourself, here is what readers say:

The short C++ section was a great refresher. The practical use of ArduinoJson in small embedded processors was just what I needed for my home automation work. Certainly worth having! Thank you for both the book and the library.

— Douglas S. Basberg

Great book for learning how to use ArduinoJson. But also a good, quick course on C++ pointers, buffers etc.

— Darryl Jewiss

I especially loved the explanations on C++ syntax. A lot of things snapped into place in my head I wasn’t expecting. Well done and thank you! Original reason I bought the book was to support the development and also to find out the design decisions on the ArduinoJson syntax which TBH got me interested in learning C++11/14 for my Arduino projects.

— Anonymous

Mr. Blanchon’s book is one of the best JSON books available to date! It gets right to the code without playing in tall grass, letting new developers get right to the good stuff.

— Daniel Travis

Just bought your Arduino JSON book on Amazon. I learned more in the hour it took me for reading your book than in three courses in University… I wanted you to know that if you write a C++ book for Arduino or any other book, I will be pleased to purchase those as well.

— Pierre Olivier Théberge

An excellent in-depth book that combines Micro-controllers and JSON instructions. This ebook was exactly what I needed to get started with the JSON, Arduino & ESP

— Avishek Hardin

I think the missing C++ course and the troubleshooting chapter are worth the money by itself. Very useful for C programming dinosaurs like myself.

— Doug Petican

Excellent approach of the programming. It goes a step forward for the programmer in C++ and enforce some knowleges. Highly recommended. Ezequiel from Argentina

— Ezequiel Pavón

I have been a casual user of the Arduino IDE for about 6 months, and tend to struggle with why I needed to define variables and constants in specific ways, and the general construction of programs in this environment. The book provides enough “why” to remove mystery from the organization of data and program spaces in the microcontroller environment to make me much more comfortable. I think that one reading of the book as fast as I could get thorough it was a good start. I intend to go through the case studies and read the book again to completely understand the material presented. The book makes forward references to material “to be covered in chapter x”. Seeing the material in those chapters will make the second reading well worth the time.

— Ron VanEtten

This book is 100% worth it. Between solving my immediate problem in minutes, Chapter 2, and the various other issues this book made solving easy, it is totally worth it.. buy it and tell other people to buy it. I build software but I work in managed languages and for someone just getting started in C++ and embedded programming this book has been indispensable.

— Nathan Burnett

I greatly enjoyed your book and found your explanations both clear and elegant. Your writing reminds me of John Skeet’s books, which always manage to cut through the complexity in a natural and intuitive manner.

— Craig Feied

Of course, purchasing the book is a great way to support the development of the library. Yes! Paying for free software is a political act; it says a lot about you: that you're grateful for the hard work, that you care about your craft, and that you are an essential piece of the open-source ecosystem.