Working more hours means getting more done. Wrong.
Stanford study: output at 70 hrs/week = output at 55. Zero. Identical. The extra 15 hours disappear.
"Working more hours means getting more done" is a myth. The supporting research is cited below. Read on for the full evidence.
"Working more hours means getting more done"
False. Stanford economist John Pencavel's 2014 analysis of output versus hours worked found that productivity per hour drops sharply after 49 hours per week.
Hustle culture has a simple answer: if you're not getting results, work harder. If others are pulling ahead, work longer. The 60-, 70-, 80-hour work week is worn as a badge in certain industries, and the equation seems obvious — more input, more output.
The Surprising Truth
Stanford economist John Pencavel's 2014 analysis of output versus hours worked found that productivity per hour drops sharply after 49 hours per week. After 55 hours, additional time produces effectively zero additional output — meaning someone working 70 hours a week produces no more than someone working 55. The extra 15 hours are simply wasted. Separately, a UCL study found that workers who regularly put in 55+ hours per week scored significantly worse on cognitive tests — equivalent to the cognitive decline associated with aging seven additional years.
What This Means for You
If you're regularly working past 50 hours, you are almost certainly not getting more done — you're just spending more time there, while degrading the cognitive capacity you'll need tomorrow. The math doesn't support grinding past 55 hours.
Primary Sources
- [1] Pencavel, J. (2015). "The Productivity of Working Hours." Economic Journal, 125(589), 2052–2076. (IZA Discussion Paper No. 8129, 2014.)
- [2] Virtanen, M. et al. (2012). "Long Working Hours and Cognitive Function." American Journal of Epidemiology, 176(12), 1105–1114. (UCL cohort study.)
Frequently Asked Questions
Does working more hours make you more productive?
Stanford study: output at 70 hrs/week = output at 55. Zero. Identical. The extra 15 hours disappear.
Is there a limit to productive work hours?
Stanford economist John Pencavel's 2014 analysis of output versus hours worked found that productivity per hour drops sharply after 49 hours per week. After 55 hours, additional time produces effectively zero additional output — meaning someone working 70 hours a week produces no more than someone working 55. The extra 15 hours are simply wasted. Separately, a UCL study found that workers who regularly put in 55+ hours per week scored significantly worse on cognitive tests — equivalent to the cognitive decline associated with aging seven additional years.
How many hours a week is too many?
If you're regularly working past 50 hours, you are almost certainly not getting more done — you're just spending more time there, while degrading the cognitive capacity you'll need tomorrow. The math doesn't support grinding past 55 hours.
How We Verified This Claim
SmartAss Facts evaluates every popular belief against a three-tier source hierarchy: primary sources (peer-reviewed research, government datasets, and court records), secondary sources (reputable journalism citing the primary), and tertiary sources (blogs and general reference sites). Only primary sources are cited. If a claim can only be traced to a blog or an unsourced assertion, it is not used.
For this myth — Working more hours means getting more done — we reviewed the cited sources above and checked the claim against the published findings. The claim was then cross-referenced with the SmartAss Facts database of over 5,000 verified facts to identify related content.
If you believe our verdict is incorrect or you have a more recent primary source that changes the analysis, the science always wins — we revise pages when the evidence warrants it. Last reviewed: 2026-10-13.
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Every claim below has been checked against published research.