Free is bio avail.
Seems pretty good number though considering being on Keto. How long you been on keto?
Here are the reference ranges for males
TESTOSTERONE, FREE
Males (adult):
20 - <25 years: 5.25-20.7 ng/dL
25 - <30 years: 5.05-19.8 ng/dL
30 - <35 years: 4.85-19.0 ng/dL
35 - <40 years: 4.65-18.1 ng/dL
40 - <45 years: 4.46-17.1 ng/dL
45 - <50 years: 4.26-16.4 ng/dL
50 - <55 years: 4.06-15.6 ng/dL
55 - <60 years: 3.87-14.7 ng/dL
60 - <65 years: 3.67-13.9 ng/dL
65 - <70 years: 3.47-13.0 ng/dL
70 - <75 years: 3.28-12.2 ng/dL
75 - <80 years: 3.08-11.3 ng/dL
80 - <85 years: 2.88-10.5 ng/dL
85 - <90 years: 2.69-9.61 ng/dL
90 - <95 years: 2.49-8.76 ng/dL
95-100+ years: 2.29-7.91 ng/dL