Many people want to know what Bible translations are most similar to the KJV or most “trustworthy.” What you’ll find is Bible translations generally fall somewhere between one of two translation categories: dynamic/functional equivalence and literal/formal equivalence. Dynamic/functional equivalence is used in translations such as the NIV and NLT, and the process involves essentially paraphrasing what the translators believe was the intended meaning of a section of Scripture. Unfortunately, that can leave the result open to being tainted by the translator’s understanding of what the passage meant.
The KJV or NKJV (more relevant to modern language but with the same translation method) as well as the ESV and NASB all use literal/formal equivalence, a method of translation that attempts as best as is possible to capture word for word translation rather than just paraphrasing the supposed meaning of a given passage. But that translation method, too, has its difficulties, since some phrases and ideas don’t translate well from one language and culture to another without further explanation. We tend to use NKJV around here for our Bible answers. There is more to the translation process for both sides, but that’s the simple explanation.