Zachariah peaked in 1992 and holds at current rank #569, with 30,668 total SSA bearers. It's the long-form biblical option in a name cluster that also includes Zachary, Zach, and Zackery. Of the group, Zachariah is the most formal, the least common, and arguably the most beautiful in full.
God Has Remembered
Zachariah is the English rendering of the Hebrew Zekharyah, meaning "YHWH has remembered" — a theophoric name combining the divine name with the root for remembrance. It appears in both the Old and New Testaments: Zechariah the prophet, and Zechariah the father of John the Baptist. The Hebrew origin is unambiguous and the meaning is genuinely beautiful if you're looking for a name that carries theological weight. The New Testament Zechariah being struck mute until his son's birth — then immediately recovering — is one of the more dramatic birth stories in scripture.
Full Name, Easy Nickname
Zachariah is eight letters and four syllables — substantial for a first name. But Zach is the obvious daily-use form, and it's one of the most natural nicknames in the American system. A child named Zachariah will almost certainly go by Zach, which means the full name is essentially a formal register used on diplomas and legal documents. Parents get the full biblical gravitas plus a nickname that fits on any playground. That combination : long formal name, short functional nickname : is a classic naming strategy that works well across ages.
Zachariah vs. Zachary
Zachary peaked at #12 in 1994; Zachariah peaked far lower and later. The difference is formality: Zachary became the standard American form, Zachariah stayed as the more deliberate biblical choice. If you want the standard spelling that everyone knows, Zachary is it. If you want the full original form with a bit more gravitas, Zachariah delivers. Both give you the same Zach at the end of the day.