Do Programmers need to know hexadecimal?
Most programmers should not bother about learning hexadecimal except those working with low-level programming languages like Assembly, C, or C++. Frontend developers will also find Hexadecimal helpful when working with colors.
In my third year of Electrical Engineering, I took a Digital Electronics class, where we learned more about Binary, Hexadecimal, ASCII, and other numbering systems. Even though hexadecimal is used a lot in the computing world, I have not used it much in my programming journey.
For most programmers, hexadecimal is not something you will use every day, and not knowing hexadecimal will not affect your programming experience or your chances of getting a job.
You can easily make reference to hexadecimal values in case you need them, there are a lot of resources that will help you to understand and convert hexadecimal to any form you need or vice versa.
DECIMAL | HEXADECIMAL | BINARY |
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 | 0 1 2 3 4 5 6 7 8 9 A B C D E F 10 11 12 13 14 15 16 17 18 19 1A 1B 1C 1D 1E 1F | 0 1 10 11 100 101 100 111 1000 1001 1010 1011 1100 1101 1110 1111 10000 10001 10010 10011 10100 10101 10110 10111 11000 11001 11010 11011 11100 11101 11110 111111 |

If you are interested in working with systems, microcontrollers, and other low-level stuff in digital electronics, being able to work with hexadecimal is a great advantage. A bonus point is there is not so much to learn about hexadecimal, they are easy to understand and convert.
WHY IS HEXADECIMAL USED BY PROGRAMMERS?
Programmers use hexadecimal because it is easier and more readable than binary. It is much easy to read 1a than 00011010, in case you are wondering, 1a (hexadecimal) is 26 in decimal, and 00011010 (binary) is 26 in decimal. You can see that 1a is easy to read and understand than 00011010.
Plus, you also save a lot of space and time using hex. You will be able to convey a lot of information without taking a lot of space using hex than binary. for example, with only 2 hexadecimal digits, you can denote any number from 0 (0) to 255 (FF).
To represent 255 (11111111) in binary, you will need 8 digits. Think of what this will be for very large numbers. You can easily see that hex is very helpful in such cases.
Though computers understand only binary, it is much easy and more convenient to work with Hexadecimal than binary. Most of the programmers will not write binary code in their programming journey.
USES OF HEXADECIMAL
Hexadecimal is useful for a number of things in programming, it can be used in machine code or assembly language to denote memory and network addresses.
Hex is also useful for colors in programming and other design software. For example, #FFAA54 helps programmers to understand how much red, green and blue has been applied.
DO PROGRAMMERS NEED TO KNOW BINARY?
Knowing binary for programmers is not necessary, but it is helpful to understand how binary works and convert binary to other numbering systems. You will most likely never write a computer instruction in binary
From the time I learned about Binary in Digital Electronics, I have been programming for years and I have never written a single digit in binary for any of my programming projects. It’s helpful to know binary but that’s just it, no need to bother.
CONCLUSION
Programmers do not need to know hexadecimal save for system programmers coding at a very low level using machine code, assembly, C, or C++. Hexadecimal is also useful for frontend developers working with colors, it helps them to understand the amount of red, green, and blue that has been applied.