XSD datatype

xs:unsignedLong

An unsigned 64-bit integer from zero to 18,446,744,073,709,551,615.

xs:unsignedLong supplies a 64-bit ceiling to nonNegativeInteger. Its upper half cannot fit in a signed 64-bit database column and no value near the top can be represented exactly by JavaScript Number.

Lexical space: Optional plus sign and digits within 0 to 18446744073709551615.
Derives from: xs:nonNegativeInteger
Category: Numeric types
Facets: minInclusive, maxInclusive, minExclusive, maxExclusive, pattern, enumeration, whiteSpace, totalDigits, fractionDigits

What validates

Every literal below is put through the schema validator on each test run, against the schema at the foot of this page.

0
+1
18446744073709551615

What does not

-1
Unsigned values cannot be negative.
18446744073709551616
One past the maximum.

What catches people out

The maximum does not fit in a signed 64-bit integer.
JavaScript Number cannot represent large valid values exactly.
Use nonNegativeInteger when no upper bound belongs in the contract.

The schema used

This is the exact schema the literals above are validated against. Paste it into the validator with one of them to see the result yourself.

schema.xsd

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
  <xs:element name="v" type="xs:unsignedLong"/>
</xs:schema>

Open the XSD validator