What should I expect from shade 5.0 Dark Brown on my current hair color, and how do starting tone and porosity affect the result?

Shade 5.0 is a standard depth-5 neutral brown with no strong warm or cool reflector. On natural level 4–6 hair it will deepen and enrich the existing tone, giving a polished, glossy brunette. On level 7 or lighter (blonde or light brown) it will deposit noticeably darker color, but the result may appear slightly warmer because the underlying pigment of lighter hair shows through. If your hair has been previously colored, the artificial pigment already inside the shaft will influence the outcome — old red or gold tones can make the result look warmer, while ash-based previous color can mute it. Porous, lightened, or chemically treated sections (highlights, perms, relaxers) absorb pigment faster and can turn out darker or more intense than the mid-lengths. That is why a strand test on a hidden section — using the exact mixture and timing you plan for the full head — is essential. Process the strand for the minimum recommended time, check, and extend in 5-minute increments up to the maximum if needed. Record the timing that gives your target shade and replicate it on the full application.