TimeConstrained—Wolfram Documentation
TimeConstrained[expr,t,failexpr]
returns failexpr if the time constraint is not met.
Details
- TimeConstrained generates an interrupt to abort the evaluation of expr if the evaluation is not completed within the specified time.
- TimeConstrained evaluates failexpr only if the evaluation is aborted.
- TimeConstrained returns $Aborted if the evaluation is aborted and no failexpr is specified.
- TimeConstrained is accurate only down to a granularity of at least $TimeUnit seconds.
- Aborts generated by TimeConstrained can be overruled by AbortProtect. »
- TimeConstrained[expr,Infinity] imposes no time constraint.
- TimeConstrained may give different results on different occasions within a single session, for example as a result of different conditions of internal system caches.
- TimeConstrained takes account only of CPU time spent inside the main Wolfram Language kernel process; it does not include additional threads or processes.
Examples
open all close allBasic Examples (2)
Scope (2)
Specify the value to return if the time constraint is reached:
Use CheckAbort inside TimeConstrained to select which parts are skipped if the limit is reached:
Properties & Relations (5)
Related Guides
Text
Wolfram Research (1988), TimeConstrained, Wolfram Language function, https://reference.wolfram.com/language/ref/TimeConstrained.html (updated 2007).
CMS
Wolfram Language. 1988. "TimeConstrained." Wolfram Language & System Documentation Center. Wolfram Research. Last Modified 2007. https://reference.wolfram.com/language/ref/TimeConstrained.html.
APA
Wolfram Language. (1988). TimeConstrained. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/TimeConstrained.html
BibTeX
@misc{reference.wolfram_2025_timeconstrained, author="Wolfram Research", title="{TimeConstrained}", year="2007", howpublished="\url{https://reference.wolfram.com/language/ref/TimeConstrained.html}", note=[Accessed: 22-February-2026]}
BibLaTeX
@online{reference.wolfram_2025_timeconstrained, organization={Wolfram Research}, title={TimeConstrained}, year={2007}, url={https://reference.wolfram.com/language/ref/TimeConstrained.html}, note=[Accessed: 22-February-2026]}