Math.trunc() Truncate
Last updated: 2026-09-09
Math.trunc() Truncate
Math.trunc removes the fractional part (truncates toward zero).
| Category | Math |
|---|---|
| ES version | ES2015 |
📝 Syntax
Math.trunc(number);⚙️ Parameters
| number | The number. |
|---|
Returns：The truncated integer.
Mutates the original：No (returns a new value)
▶ Example
Edit the code, press Run, and see the result in the output panel:
Output：
4
-4
-5
4💡 Tip trunc and floor are the same for positives; differ for negatives.
ℹ️ info Math.trunc (ES2015) is semantically clearer than Math.floor for truncation.
🌐 Browser support
| Browser |  Chrome |
 Edge |
 Firefox |
 Safari |
 Opera |
|---|---|---|---|---|---|
| Math.trunc() | ✓ v34 | ✓ v12 | ✓ v32 | ✓ v9 | ✓ v21 |
| Supported by all modern browsers | |||||
🏷️ Related Items
💡 Related Cases
More case studies coming soon — check back later.
📚 Related Tutorials
❓ FAQ
Qtrunc vs floor?
Atrunc goes to zero; floor to -infinity. Same for positives.
QWhen was trunc added?
AES2015 (ES6).
QHow many rounding methods?
AFour: ceil, floor, round, trunc.
