I edited this a bit so that all the numbers will be all slightly different from decimal.

Here is just a proposed way of counting in dozenal that I think would be easier for people to learn who don’t understand it. It uses the number names that we already use in our everyday life with some adjustments to fit the dozenal system. If we want the world to use the dozenal system, changing names of numbers to things like dek, el and do would confuse people and make them not want to use it. Instead of using teen and ty as a suffix (as in ten), you would use zeen for the teens, zy for the tys and zen for the thousands and millions as a suffix (as in doZEN).

It goes like this: one 1, two 2, three 3, four 4, five 5, six 6, seven 7, eight 8, nine 9, ten Λ, (e)leven Ɛ, twelve / dozen 10, onezeen 11, twozeen 12, thirzeen 13, fourzeen 14, fivzeen 15, sixzeen 16, sevenzeen 17, eightzeen 18, ninezeen 19, tenzeen 1Λ, (e)levenzeen 1Ɛ, twenzy 20, twenzy-one 21, twenzy-two 22, thirzy 30, fourzy 40, fivzy 50, sixzy 60, sevenzy 70, eightzy 80, ninezy 90, tenzy Λ0, (e)levenzy Ɛ0, one gross 100, one thouzen 1,000, twelve thouzen / one dozen thouzen 10,000, one gross thouzen 100,000, one millzen 1,000,000, twelve millzen / one dozen millzen 10,000,000, one billzen 1,000,000,000, one trillzen 1,000,000,000,000, and so on.

While you are saying the numbers out loud, Ɛ would be pronounced (and maybe even spelt) "leven" so there are only two syllables which makes saying it a bit easier and faster. So ƐƐ would be pronounced levenzy-leven.

Continuing with even bigger numbers, they would go millzen 10^6, billzen 10^9, trillzen 10^10, quadrillzen 10^13, quintillzen 10^16, sextillzen 10^19, septillzen 10^20, octillzen 10^23, nonillzen 10^26, decillzen 10^29, onzillzen 10^30, dozillzen 10^33, undozillzen 10^36, and so on.

So 10,382,620,9Λ5,6ƐƐ would be pronounced twelve trillzen three gross eightzy-two billzen six gross twenzy millzen nine gross tenzy-five thouzen six gross levenzy-leven.

Instead of saying twelve, you could use dozen as an alternative but they would mean the same thing. 4 8=twelve but there are one dozen eggs in an egg carton. Just like we already do.