The 1965 forecast and the 1975 revision
In a short 1965 article in Electronics, Gordon Moore, then research director at Fairchild Semiconductor, observed that the number of components on the lowest-cost integrated circuit had roughly doubled every year and predicted the trend would continue for at least a decade. In 1975 he revised the pace to a doubling every two years. The often-quoted "18 months" is usually traced not to Moore but to his Intel colleague David House, who combined transistor counts with speed gains to estimate performance growth. Carver Mead coined the name "Moore's law," but it is an observation about a technological trend, not a physical law.
Why it lasted so long
Dennard scaling explains much of the trend's longevity. Robert Dennard and colleagues (1974) showed that as transistors shrink, voltage and current can shrink with them, keeping power density per unit area constant, so chips became smaller, faster and more efficient together. Because the industry adopted the pace as a shared target through the International Technology Roadmap for Semiconductors, Moore's law worked partly as a self-fulfilling prophecy. The economist William Nordhaus (2007) measured how the cost of computation fell dramatically year after year for decades, and Dale Jorgenson (2001) identified it as a major source of the US productivity surge in the 1990s. Cheap computation became the foundation of artificial intelligence and the platform economy.
Slowdown and life after Moore
In the mid-2000s leakage current and heat broke Dennard scaling, clock speeds stalled, and the industry turned to multicore designs. Esmaeilzadeh et al. (2011) described "dark silicon," where power limits prevent large parts of a chip from running at once. As features neared atomic scale, costs soared, and Nature (2016) reported that the industry roadmap would no longer target Moore's law. Bloom et al. (2020) used it as a case study in "ideas getting harder to find," estimating that sustaining the trend required many times more researchers than in the 1970s. Leiserson et al. (2020) argued that future gains will come from "the top": software performance engineering, algorithms and specialized hardware. Thompson and Spanuth (2021) analyzed the shift from general-purpose computers to specialized chips.
FAQ
- Is Moore's law dead?
- It depends on the definition. Transistor density is still rising, but more slowly and at higher cost, and there is broad agreement that the classic gains in clock speed and power efficiency faded after the mid-2000s.
- Is Moore's law 18 months or two years?
- Moore's own 1975 revision was two years. The 18-month figure spread from a colleague's description of performance growth.
Sources reviewed: 2026-10-26
References
- Moore, G. E. (1965). Cramming more components onto integrated circuits. Electronics, 38(8), 114–117.
- Moore, G. E. (1975). Progress in digital integrated electronics. In IEEE International Electron Devices Meeting Technical Digest (pp. 11–13).
- Dennard, R. H., Gaensslen, F. H., Yu, H.-N., Rideout, V. L., Bassous, E., & LeBlanc, A. R. (1974). Design of ion-implanted MOSFET's with very small physical dimensions. IEEE Journal of Solid-State Circuits, 9(5), 256–268.
- Mack, C. A. (2011). Fifty years of Moore's law. IEEE Transactions on Semiconductor Manufacturing, 24(2), 202–207.
- Nordhaus, W. D. (2007). Two centuries of productivity growth in computing. Journal of Economic History, 67(1), 128–159.
- Jorgenson, D. W. (2001). Information technology and the U.S. economy. American Economic Review, 91(1), 1–32.
- Esmaeilzadeh, H., Blem, E., St. Amant, R., Sankaralingam, K., & Burger, D. (2011). Dark silicon and the end of multicore scaling. In Proceedings of ISCA 2011 (pp. 365–376).
- Waldrop, M. M. (2016). The chips are down for Moore's law. Nature, 530(7589), 144–147.
- Leiserson, C. E., Thompson, N. C., Emer, J. S., et al. (2020). There's plenty of room at the top: What will drive computer performance after Moore's law? Science, 368(6495), eaam9744.
- Bloom, N., Jones, C. I., Van Reenen, J., & Webb, M. (2020). Are ideas getting harder to find? American Economic Review, 110(4), 1104–1144.
- Thompson, N. C., & Spanuth, S. (2021). The decline of computers as a general purpose technology. Communications of the ACM, 64(3), 64–72.