HEAVY metal and horror fans' heads are spinning after claims of a beastly biblical mistake.

New research suggests the accepted devil's number, 666, is well off the mark.

The revelations -- from the book of the same name -- came during tests on ancient biblical fragments.

New photographic techniques are claimed to reveal the biblical number of the beast is 616, not 666.

The third-century fragment was part of a hoard from historic dumps outside Oxyrhynchus, Egypt.

University of Birmingham professor David Parker said the fragment from the oldest surviving New Testament had the number 616.

It was in a code where letters in names are given numerical values.

And Drew Sinton, proprietor of Melbourne's Haunted Bookshop, says some will find 616 a cross to bear.

"They wouldn't like it," he said. "It's in all the rock songs, and even the occult people . . . well, it just doesn't look as good, does it?"

But he said many would just ignore the research.

"People believe what they want to believe, and what evidence is going to convince them otherwise?" he said.

The number 666 has been found by believers hidden in such diverse places as computer bar codes and Bill Gates's name.

Melbourne Anglican theologian Dr Charles Sherlock described 666 as "an iconic little number", but he said 616 had long been considered possible.

"It's well known. It's a standard variant," he said. "It's normally thought of as about 20 per cent probability."

He said if the ancient fragment pointed to 616, the probability that was correct would increase.

"Six plus six plus one is 13, and that's the death card in the Tarot," he said.