ENIAC Performance Calculator
Estimate the computational power and energy consumption of the historic ENIAC computer compared to modern systems
Calculation Results
ENIAC: The First General-Purpose Electronic Computer
The Electronic Numerical Integrator and Computer (ENIAC) was the first general-purpose electronic computer, completed in 1945 at the University of Pennsylvania’s Moore School of Electrical Engineering. Funded by the U.S. Army for ballistic calculations during World War II, ENIAC represented a monumental leap in computing technology, replacing mechanical calculators with electronic speed.
Key Technical Specifications of ENIAC
- Size: 100 feet long, 10 feet high, 3 feet deep
- Weight: 30 tons (27,216 kg)
- Components: 17,468 vacuum tubes, 7,200 crystal diodes, 1,500 relays, 70,000 resistors, 10,000 capacitors
- Power Consumption: 150 kilowatts (enough to power 150 modern homes)
- Clock Speed: 100 kHz (0.1 MHz)
- Memory: 20 accumulators (each could store a 10-digit decimal number)
- Programming: Physical rewiring via patch cables and switches (no stored program)
- Performance: 5,000 additions/second, 357 multiplications/second, 38 divisions/second
Historical Context and Development
ENIAC’s development began in secret in 1943 under the code name “Project PX” at the University of Pennsylvania’s Moore School. The primary designers were John Mauchly and J. Presper Eckert, with a team of engineers that included notable figures like Jean Bartik and Kathleen McNulty, who were among the first programmers.
The machine was officially unveiled to the public on February 14, 1946, though it had been operational since late 1945. Its first major calculation was for the hydrogen bomb project in December 1945, performing computations that would have taken human computers months in just seconds.
Architectural Innovations
- Electronic Speed: Unlike previous mechanical computers (like the Harvard Mark I), ENIAC used vacuum tubes for electronic switching, achieving speeds 1,000 times faster than electromechanical relays.
- Decimal System: Operated in base-10 (decimal) rather than binary, which was more intuitive for human operators at the time.
- Parallel Processing: Could perform multiple operations simultaneously across its 20 accumulators.
- Modular Design: Consisted of 40 independent panels, each performing specific functions (e.g., accumulators, multipliers, dividers).
Programming ENIAC
Programming ENIAC was a physical process that could take days:
- Operators used patch cables to connect different functional units.
- Switches were set on the machine’s panels to control operations.
- The “master programmer” (often Jean Bartik) would oversee the setup, which could involve thousands of connections.
- Debugging required physically checking each connection and vacuum tube for failures.
This labor-intensive process highlighted the need for stored-program computers, leading directly to the development of EDVAC (Electronic Discrete Variable Automatic Computer) and the stored-program concept proposed by John von Neumann.
ENIAC vs. Modern Computers: A Performance Comparison
| Metric | ENIAC (1945) | Modern Smartphone (2023) | Performance Ratio |
|---|---|---|---|
| Additions per second | 5,000 | ~10 billion | 2 million × faster |
| Multiplications per second | 357 | ~5 billion | 14 million × faster |
| Memory Capacity | 200 digits (20 × 10-digit numbers) | 6-12 GB RAM | ~300 million × more |
| Power Consumption | 150 kW | 2-5 W (idle) | 30,000 × more efficient |
| Physical Size | 1,800 ft³ (167 m³) | 0.05 ft³ (1.4 L) | 36,000 × smaller |
| Cost (inflation-adjusted) | $6.8 million (1946) | $1,000 | 6,800 × cheaper |
Legacy and Impact on Computing
ENIAC’s influence extends far beyond its original military purpose:
- First General-Purpose Computer: Proved that electronic computers could solve a wide range of problems, not just specialized calculations.
- Catalyzed the Computer Revolution: Directly led to the development of EDVAC, UNIVAC, and the stored-program architecture that defines modern computers.
- Women in Computing: The ENIAC programmers (mostly women) became pioneers in software development, though their contributions were often overlooked until recent decades.
- Public Awareness: ENIAC’s 1946 unveiling marked the first time the public saw an electronic computer, sparking imagination about the future of technology.
- Educational Impact: The Moore School Lectures (1946) based on ENIAC’s design spread computing knowledge globally, influencing computer science education.
Preservation and Where to See ENIAC Today
While the original ENIAC was dismantled in 1955, several parts survive in museums:
- Smithsonian National Museum of American History: Displays five of ENIAC’s original accumulators and other components.
- University of Pennsylvania: Houses one accumulator panel and documentation in its engineering school.
- Computer History Museum (Mountain View, CA): Features a reconstruction of an ENIAC accumulator and extensive archives.
- U.S. Army Ordnance Museum: Contains some original ENIAC components related to its military applications.
A full-scale working replica of an ENIAC accumulator was built in 1997 to celebrate the 50th anniversary of its unveiling, demonstrating the machine’s operations to modern audiences.
Common Misconceptions About ENIAC
| Misconception | Reality |
|---|---|
| ENIAC was the first computer ever built. | Earlier computers existed (e.g., Z3, Colossus, Harvard Mark I), but ENIAC was the first general-purpose, fully electronic computer. |
| ENIAC was binary. | ENIAC used decimal arithmetic (base-10) because it was designed for human operators familiar with decimal numbers. |
| ENIAC had no programming language. | While it lacked stored programs, it had a sophisticated system of wiring and switches that functioned as a form of “hardware programming.” |
| ENIAC was only used for military purposes. | After the war, ENIAC was used for weather prediction, atomic energy calculations, and even early AI research. |
| ENIAC was unreliable due to vacuum tubes. | Despite having 17,468 tubes, ENIAC had an uptime of ~97% thanks to careful engineering and redundant circuits. |
ENIAC in Popular Culture
ENIAC’s iconic appearance and historical significance have made it a frequent subject in media:
- Films: Featured in documentaries like “The Computers” (2014) and dramatized in “Hidden Figures” (2016).
- Literature: Central to novels like “ENIAC: The Triumphs and Tragedies of the World’s First Computer” by Scott McCartney.
- Art: Inspired works like the ENIAC-inspired sculpture at the University of Pennsylvania.
- Music: Referenced in songs like “ENIAC” by the band Information Society.
- Video Games: Appears in games like “Civilization VI” as a wonder representing the computer age.