King Camp Gillette

King Gillette revolutionized personal grooming and built an empire worth approximately $405 million in today's dollars—with his peak net worth reaching closer to $700 million around 1915. He patented the safety razor in 1904 and combined genius engineering with aggressive marketing, creating one of the first recurring revenue models in consumer products. The disposable blade concept meant customers needed replacements constantly, turning a one-time purchase into lifetime consumption.

Gillette's business acumen matched his invention brilliance. He didn't just patent the razor; he built a vertically integrated manufacturing operation, established distribution networks across America and Europe, and pioneered brand advertising before most companies understood its power. By 1910, his company was selling over 90 million razors annually and millions of blade packs. He also invested heavily in real estate and held various executive positions that diversified his wealth beyond the razor business alone.

Compared to modern billionaires, Gillette's wealth accumulation was even more impressive given the era's smaller overall economy and higher tax burdens in his later years. While today's tech moguls measure worth in tens of billions, Gillette dominated an entirely new category he invented—a rare feat. His $405 million adjusted fortune represents genuinely transformative innovation that became a daily necessity for billions, making him not just wealthy but historically consequential in reshaping global consumer behavior.