Equation for Converting Pixels to EMs

• 1em = 10px
• OR
• target / context = result (Target = target font size, context = font size of containing element)

Example

Here is an h1 using pixels:

h1 {
  font-size: 30px;
  font-weight: bold;
}

We can convert that px value to ems:

30px / 10px (standard font size) = 3em

Result:

h1 {
  font-size: 3em; /* 30x/10px */
  font-weight: bold;
}