Hexadecimal – Lesson 2


So today we are talking about hexadecimal. No it’s not the virus from the cartoon Reboot

Hexadecimal - reboot

Hexadecimal – the multifaced virus from the show reboot

I mean the lovely programing language that is several times used in coding.

If you check out lesson one (https://plus.google.com/u/0/110772295533413912899/posts/NqiuVu2Kjg7), and learned something from there you will know by now that decimal uses numbers to define itself. Numbers are limited to 10 possibilities ( 0 1 2 3 4 5 6 7 8 9). This is where hex becomes quite unique. There are 16 possibilities. How? well simple. It cheats and uses letters as well. Namely A to F. So the 16 possibilities (0 1 2 3 4 5 6 7 8 9 a b c d e f ) allow for 256 possibilities (16 x 16) using just 2 characters. Remember decimal ranges ? 0 to 255. Yeah they relate there . But we will leave these relations for more advanced lessons.

For now let’s limit ourselves to converting from hex to ASCII.
So let’s discuss ranges for letters and numbers
A- Z will be 41-5a 
Please notice this the letters IJKLMNOP in hex are 49 4a 4b 4c 4d 4e 4f 50. The reason I am point out this is for you to see how the sequence in hex works.
So for the rest a-z (61-7a) and the numbers 0-9 (30 39)

4c 65 73 73 6f 6e 32
So if you look at this you should immediately recognize the encoding as hex not only because of the ranges but because of the letters e and f there. Hex codes major recognition is those letters (a-f). Keep that in mind.
To translate Hex to ASCII once again I recommend http://www.asciitohex.com

Ok enough with the chitchat and down to our exercise of the day.
It will be similar to the one from yesterday just with a little…twist
Have fun and enjoy your lvl 1 resonator :)
*NOTE* – The final result is web link not a passcode to put in ingress. The reward you get at the end is just for fun and to help you learn how to decode passcodes in the future ;)


About Author

Jack Frost. As blue as his ingress alignment, as cold as his country.The world around might not be what it looks like , but I want to try to help others decode those hidden truths


  1. When I enter the code on that site, it keeps giving me similar codes, and no URL at all. I got this:

    • Like a said a little twist. Have a look at the ranges and what you got and you might realize you need to face this puzzle from a different angle

    • yep well done, you are in the right path :)
      Hope you keep enjoying the future lessons and they are useful for your decoding passcode future

  2. Hexadecimal is just base 16 numbering system. As long as you know the base 10 (our normal numbering system, decimal) equivalent for the letter or number character, you are good!

    For example,

    The character 0 = 48 in decimal

    To get the base 16 equivalent, all you do is divide by the highest power of 16 (1, 16, 256, etc) and keep repeating until your remainder is less than 16. The answers you get from division and the final remainder will convert to base 16 notation (0-9, a-f). You should then record your division results using a column format below (x represents results), where going left to right, you start from the highest power of 16 you divided by and go to the remainder at the end (the 1 column). For the characters we are interested in, we will probably not use 256.

    … 256 16 1
    … x x x

    In the example, 48 is clearly divisible by 16. 3 times exactly! There is no remainder.

    16 1
    3 0

    Therefore, the character 0 = 48 in decimal = 30 in hexadecimal.

    A more complex example would be the character z = 122 in decimal.
    122/16 = 7, remainder of 10

    16 1
    7 10 (equates to a in hexidecimal)

    Therefore, the character z = 122 in decimal = 7a, in hexadecimal!

    You can easily check your results by going backwards by using multiplication and then adding the results. Using column format for the last example,
    7 a (10)
    x16 1
    = 112 + 10 = 122!

    That’s some of the background for you. The tool should be used for multiple conversions!

    • Thanks for very detailed explanation. Extra info is always welcomed
      But try to use this knowledge while decoding some of the codes and all you will get will be “already redeemed”

    • With this, if I’m reading it correctly, to find the hex from decimal is to divide by 16, multiply by 10 and round to the next number and there’s your hex? I guess I’m trying to figure an easier way to understand hex because decimal is simpler in a sense. The only thing is outside of the numbers given in lesson one I don’t know what they symbolize and when I play with the numbers by randomly choosing them in the tool given, they are a symbol of something. My major question would be how do you know when to split a number especially in decimal and hex? The only way I would know when to split would be with a tip ahead of time by someone telling me, they are all letters.

  3. Pedro Correia on

    By inserting this -> 45474e4d152f6c762e6f6f76 I get this -> EGNM/lv.oov but it takes me nowhere :-( Am i even close?…

  4. I’m sorry, I can’t work this out correctly. Can you give me a little hand?
    I spaced it out so that it works, but as you’ll see, I can’t space it properly because I’m confused.
    45 47 e4 d4 15 f2 c6 76 e2 f6 f6 76
    I think it’s missing a few characters, but I’m doing it exactly according to the post. Am I meant to delete a few characters?

  5. Jack Frost put a twist to it. Have you noticed the position of all the letters in the pairs in his explanation versus those in the “lesson” code? :)

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Hexadecimal – Lesson 2

by Jack Frost time to read: 1 min