When was the Bible written? Across roughly 1,500 years, not in one sitting and not in one century. The Old Testament took shape over hundreds of years, with the earliest material reaching back before 1000 BC and much of it settling into something close to its final written form during and after the Babylonian exile in the 500s BC. The New Testament, by contrast, was written inside a single lifetime, roughly AD 48 to AD 100.
That gap between the two halves is most of the story. The Old Testament is layered: oral tradition, early writing, editing, and compiling stretched across centuries. The New Testament is tight, written down within about two generations of the events it describes.
When the Old Testament was written
Jewish and Christian tradition places Moses writing the first five books, Genesis through Deuteronomy, sometime in the 1400s or 1200s BC, depending on which date for the Exodus a reader accepts. That is the traditional dating, and plenty of readers still hold it.
Most modern scholars read the evidence differently. The common academic view is that these books, and much of the rest of the Old Testament, were written across many centuries by different hands, then edited and compiled into something close to their current form during and after the Babylonian exile, in the 500s and 400s BC. Some material is likely older than that (poetry embedded in Judges and Exodus is often considered some of the oldest writing in the whole collection), while other material, like parts of Chronicles, was clearly written after the exile, looking back on it.
Both pictures, tradition and mainstream scholarship, agree on one thing: the Old Testament was not written all at once. It grew.
The oldest copies that actually survive
No original manuscript of any Old Testament book survives. What exists are copies of copies. The oldest substantial copies we have are the Dead Sea Scrolls, a collection of Jewish manuscripts found in caves near the Dead Sea starting in 1947. They date from about the 3rd century BC to the 1st century AD and include fragments or full copies of nearly every Old Testament book. More on what the Dead Sea Scrolls are and why they matter is here.
Those scrolls matter because they let scholars compare an ancient copy against the text used centuries later, and the match is close. That does not tell us when a book was first written. It tells us the text was already stable well before the time of Jesus.
When the New Testament was written
This is the part of the Bible with the tightest dating, since it covers a much shorter window and several of its authors describe real events and real people that can be checked against other historical sources.
Paul’s letters are the earliest New Testament documents, written from roughly AD 48 to the early AD 60s, within about 20 years of Jesus’s death. The four Gospels come later. Mark is commonly dated to around AD 65 to 70, Matthew and Luke to the AD 80s or 90s, and John last, sometime before AD 100. A minority of scholars argue for earlier dates on some or all of the Gospels, but AD 65 to 100 is the common range. Revelation is usually dated around AD 95, near the end of the first century, though a smaller number of scholars place it earlier, before AD 70.
Put together, the entire New Testament was written within roughly 50 years, all of it inside the first century AD. Who actually wrote each of these books is covered in more depth here.
When it became “the Bible”
Writing a book and recognizing it as scripture are two different steps. Individual Old Testament books were treated as authoritative by Jewish communities well before the time of Jesus. New Testament books circulated and were read in churches for decades before anyone wrote down a formal list of which ones counted.
By the 4th century AD, church leaders and councils were producing lists of New Testament books that closely match what is in Bibles today. That is not the moment those books were written. It is the moment their status stopped being an open question in practice and started being formally recorded.
Where that leaves you
The Bible is not one book with one write date. It is a library, and the honest answer to “when was it written” depends on which shelf you mean. The Old Testament is centuries of writing, editing, and compiling, most of it settled into something close to its current shape by the time of the exile. The New Testament was written fast by comparison, inside a single century, by people close to the events themselves.
Knowing the timeline does not settle what any of it means. It tells you what you are holding: a very old, very layered Old Testament, and a New Testament written by people who were, historically speaking, still within living memory of what they described. For how those two halves differ beyond just their dates, here is the fuller breakdown of Old Testament versus New Testament.