Zumpe was born in Fürth, suburbs of the Free Imperial City of Nuremberg in Franconia (modern Germany). He likely apprenticed with a renowned organ builder and early fortepiano maker, Gottfried Silbermann (1683—1753). During the Seven Years' War, when Johann Christoph was in his thirties, he fled to England. A few German instrument makers also relocated to London at the time, later colloquially known as "twelve Apostles" (including Americus Backers (ca.1740 — post-1778), one of the inventors of the "English action.") Several biographers repeated Charles Burney's 1918 claim from Rees's Cyclopædia that Zumpe, supposedly, worked for harpsichord maker Burkhard Shudi (1702—1773) soon after settling in London, even though no further documentary evidence of their collaboration exists.

Circa 1761, Johannes Zumpe launched an independent workshop on Princes Street, Hanover Square, under "the Golden Guittar sign" (which led some researchers to conclude he was also making guittars, so-called "English guitars.") New business soon gained traction, visited by [url=https://discogs.com/artist/95546]Mozart[/url]'s family in 1764–65 during their tour of British musical instrument shops. After 1766, Zumpe focused primarily on square pianos, compact rectangular-shaped instruments with a compass of about five octaves. To make his product more affordable, Johann Christoph pioneered the "English single" action, much simpler than the original [url=https://discogs.com/artist/6256125]Cristofori[/url] mechanism. According to surviving insurance policies, Johannes Zumpe was a prolific entrepreneur and owned multiple properties across London.

Even though Zumpe got married in 1760, he never had children and thus relied on business partners. Between 1769 and 1778, he worked with Gabriel Gottlieb Buntebart (1726—1794), operating under a new "Queen's Arms" shop sign. In the early 1780s, Zumpe began collaborating with brothers Frederick and Christian Schoene, fellow German immigrants, who soon took over his business. They established a new company, "Schoene & Co," but kept brandishing Zumpe's name, always printed in thicker typeset in the center of their nameplates. (Presumably, Schoene paid licensing fees to retired Johannes.)