Boundary Value Generator
Picks a standard boundary value used in software testing — zero, a maximum integer, an empty string, NaN — for exercising the edges of a function's input range.
What you'll get
This generator draws from a hand-checked list of 22 entries. Here is a spread of 6 of them, so you can see the style before you generate:
- 0 — the zero/empty boundary
- -2147483648 — minimum 32-bit signed integer
- 255 — maximum unsigned 8-bit value
- an empty string ""
- null
- -Infinity
A fixed sample of the list, not a live draw — your own results are picked at random from all 22, without repeating until the list runs out. Original authoring for Generate Random — standard numeric/string boundary values used in software testing.. Last reviewed 2026-07-18.
How to use this tool
- Press generate for a value.
- Use it as a test case, or generate again.
Common use cases
- Boundary-value-analysis testing
- Filling a test-data checklist
- Teaching testing fundamentals
Practical tips
- Test the value either side of a boundary as well as the boundary itself — off-by-one errors hide exactly there.
- Empty, zero, negative and maximum are the four that catch most real defects, so cover them before the exotic cases.
Entries are chosen with your browser's cryptographic random number generator, so every entry on the list is equally likely. How Generate Random works.
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