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TimeUsed[]

gives the total number of seconds of CPU time used so far in the current Wolfram System session.

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TimeUsed

TimeUsed[]

gives the total number of seconds of CPU time used so far in the current Wolfram System session.

Details

  • TimeUsed records only CPU time actually used by the Wolfram Language kernel. It does not include time used by external processes called by the kernel. It also does not include time during pauses produced by Pause.
  • TimeUsed is accurate only down to a granularity of at least $TimeUnit seconds.

Examples

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Basic Examples  (2)

CPU time used by a Wolfram Language kernel:

Wolfram Language code: TimeUsed[]

Get time between function evaluations:

Wolfram Language code: {res, {times}} = Reap[Sqrt[2] - x /. FindRoot[x ^ 2 - 2, {x, 1.}, WorkingPrecision -> 1000000, EvaluationMonitor :> Sow[TimeUsed[]]]]

Almost all of the time is spent in the last few evaluations because the precision is adaptive:

Wolfram Language code: ListPlot[{times - times[[1]], Join[{0}, Differences[times]]}, PlotRange -> All]

Scope  (1)

Get time used by function evaluations and the rest of a computation:

Wolfram Language code: f[a_ ? NumberQ] := Module[{x, t, r}, Sow[TimeUsed[]];r = First[x[1] /. NDSolve[{x''[t] + (a / 1000 + Exp[-1000 t ^ 2]) == Sin[a t], x[-1] == 0, x'[-1] == 0}, x, {t, -1, 1}, Method -> "StiffnessSwitching", WorkingPrecision -> 32, MaxSteps -> Infinity]];Sow[TimeUsed[]];r]
Wolfram Language code: Short[{res, {times}} = Reap[Quiet[FindRoot[f[a], {a, 1000}, WorkingPrecision -> 32]]], 16]

The total computation time:

Wolfram Language code: times[[-1]] - times[[1]]

Get the evaluation times:

Wolfram Language code: evals = Apply[(#2 - #1)&, Partition[times, 2], {1}]; {Total[evals], Mean[evals]}

Evaluations tended to be faster near the root:

Wolfram Language code: ListPlot[evals]
Wolfram Research (1991), TimeUsed, Wolfram Language function, https://reference.wolfram.com/language/ref/TimeUsed.html.

Text

Wolfram Research (1991), TimeUsed, Wolfram Language function, https://reference.wolfram.com/language/ref/TimeUsed.html.

CMS

Wolfram Language. 1991. "TimeUsed." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/TimeUsed.html.

APA

Wolfram Language. (1991). TimeUsed. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/TimeUsed.html

BibTeX

@misc{reference.wolfram_2026_timeused, author="Wolfram Research", title="{TimeUsed}", year="1991", howpublished="\url{https://reference.wolfram.com/language/ref/TimeUsed.html}", note=[Accessed: 13-June-2026]}

BibLaTeX

@online{reference.wolfram_2026_timeused, organization={Wolfram Research}, title={TimeUsed}, year={1991}, url={https://reference.wolfram.com/language/ref/TimeUsed.html}, note=[Accessed: 13-June-2026]}