Find holes in an integer list
Paste sorted whole numbers with one value on each line. The report lists every missing range between adjacent values and totals the missing integers without expanding an enormous range.
Ascending or descending, including large values
The first non-equal pair establishes the order. Every following pair must continue in that direction. Values use JavaScript BigInt, so identifiers and counters larger than normal safe-number precision remain exact. Repeated values and changes in direction are reported as errors.
Output limits and privacy
At most 100 individual gap ranges are displayed, while the exact total and full gap count are still reported. Blank input lines are ignored. Your number list is processed only in this browser tab.