4-6 oz Portion Size for Meat

I'm trying a new diet and it says i should eat 4-6 oz chicken, fish, beef, etc. However, I do not own a food scale and as such I am unsure how big a piece of meat 4-6 oz is. Any visualization aids or approximate measurements would be helpful.

Thanks

the size of your fist is a good measure for 6 oz. not the thickness, but the diameter.

If you had to guess, or maybe you know, about how thick is a 4-6 oz slice (assuming the thickness is uniform)?

slightly less or equal to the thickness of one of your fingers.

Normally meat is purchased by weight. Just divide total weight purchased by portion size (in ounces). Eye ball it, pretty basic, really. Or buy a scale if your not good at estimating. A deck of cards is around 4 or 5 ounces.

Good advice everyone. Thank you for your help.

3oz is about the size of a deck of playing cards