TupleHashXOF256
Generate TupleHashXOF256 output from one value or ordered line-separated elements with selectable encoding, length, and customization. Expand to read more.
What is TupleHashXOF256?
TupleHashXOF256 is the extendable-output form of TupleHash256 based on cSHAKE256. This calculator reads text as a single tuple element or as multiple elements separated by lines, then returns the requested number of output bits in the selected encoding. Identical elements and options produce the same value.
How to use this hash calculator
Choose Single value to hash the whole textarea as one element, or Multiple values (one per line) to treat each line as its own element. Select the input encoding, digest format, and customization string, then calculate the hash. Use Hex when comparing technical test vectors, or Base64 when a compact text representation is more convenient.
Result example
NIST sample vectors often use multiple binary strings as separate tuple elements. Switch to line mode and enter one Hex string per line. Concatenating those strings into one element will not match the sample, because TupleHash encodes the length of every element.
Important limitations
TupleHashXOF256 output intentionally differs from ordinary TupleHash256, even when the input, customization string, and displayed output length are the same. The two modes encode the requested output length differently. Element order matters. In line mode, each line is one element, including empty lines created by consecutive or trailing newlines. An element cannot itself contain a line break in this mode because line breaks define tuple boundaries.
TupleHashXOF is specified in NIST SP 800-185.
Frequently asked questions
Why does my result differ from another tool?
Check the input mode, every element’s bytes and encoding, the element order, customization string, and output length. Also confirm that the other tool uses TupleHashXOF256 rather than TupleHash256.
Can I use the result to verify data?
Yes, if you compare it with a trusted TupleHashXOF256 value supplied independently for the same elements and parameters. Matching an untrusted digest copied from the same location does not establish authenticity.