Born in Dawley, Shropshire, Webb developed his swimming skills as a child while playing in the River Severn.

After graduating, he began a three-year apprenticeship with the Rathbone Brothers of Liverpool, during which he sailed internationally across various trade routes to countries including China, India, Hong Kong, Singapore and Yemen.

After completing his second mate training in 1865, Webb worked for ten years aboard different ships and for multiple companies.

In 1875, on his second attempt, Webb gained fame by successfully swimming the English Channel from Dover, England, to Cap Gris-Nez, France.

[8] Webb enjoyed showing off in front of his friends and reading sea stories, with the book Old Jack by W. H. G. Kingston inspiring him to become a seaman.

He would leap off the yardarm into the sea, and earned an extra £1 per day for anchoring near a wreck, and then swimming back to shore—a job which the other sailors were too afraid to do.

[22] During the voyage, he attempted to rescue a man overboard by jumping into the cold mid-Atlantic Ocean while the ship was travelling at 14.5 kn (26.9 km/h; 16.7 mph).

[23][3] The man was never found, but the passengers of the Russia gave Webb a purse of gold[24] and upon returning home, he learned that his attempted rescue had won him the first Stanhope Medal and made him a hero in the British press.

[28] Before returning to Watson's office on Fleet Street, he tested himself by swimming to the Varne Lightvessel and back again, a distance of 13 miles (21 km).

Watson was surprised by Webb's return and introduced him to Fred Beckwith, a coach at Lambeth Baths in south London.

[27][30] Watson and Beckwith arranged a secret trial of Webb, watching him swim breaststroke down the Thames from Westminster Bridge to Regent's Canal Dock.

[37] On 3 July Beckwith organised a spectacle with Webb attempting a 20-mile (32 km) swim from Blackwall to Gravesend along the River Thames, which he finished in 4 hours and 52 minutes.

[3][38] Although Webb gained media attention for the feat,[38] low public interest on the rainy day meant Beckwith lost money.

Should he by chance succeed, which is extremely improbable, it would be cruel that one who would undoubtedly have performed the greatest athletic feat on record should be a loser by the event.Webb's next swim was a 20-mile journey from Dover to Ramsgate.

[45] In August Webb moved from London to the Flying Horse Inn in Dover to begin final preparations.

[50][1] According to Dolphin from the Illustrated Sporting and Dramatic News, during the swim, he tried an early form of goggles without a seal, which he called "barnacles", but they did not work.

He consumed cod liver oil, beef tea, brandy, coffee and ale, but did not stop long for each feed to preserve body heat.

[64] The Maid of Kent returned with a rowing boat containing eight people to shield Webb from the wind and rain,[65] and the crew sang the tune "Rule, Britannia!".

[70] After meeting the crowds at the hotel and touring a lace factory,[71] Webb and George Ward boarded the flag-decorated Castalia for their return to England.

[78] He accepted invitations to visit the Lord Mayor of London, receive an ovation at the Royal Cambridge Music Hall and have his portrait drawn.

[84] Surgeon Sir William Fergusson called Webb's feat "almost unrivalled as an instance of human prowess and endurance", and noted his body's likely ability for vasoconstriction to prevent heat loss.

[61] He began lecturing on his career and swimming-related topics,[90][91] where he opposed the common Victorian practice of forcefully dunking children, suggesting instead they learn by experimenting for themselves in shallow water.

Two white buoys were placed half a mile apart; Webb was tasked with swimming around them 20 times in regular trunks, while Boyton completed 25 laps in his suit.

The details of the race are unclear, but the referee refused to declare a winner and later accused Webb of cheating by swimming to shore and running across the beach.

[111] On 27 April 1880, Webb and Madeleine Kate Chaddock married at St Andrew's Church, West Kensington, and they later had two children, Matthew and Helen.

[111] Webb's last competitive swim was in March 1883, when he raced 20 miles (32 km) at Lambeth Baths against Willie Beckwith.

[120] Fred Beckwith and Watson tried to dissuade him, with Watson later saying:[111][121] As we stood face to face I compared the fine, handsome sailor, who first spoke to me about swimming at Falcon Court, with the broken-spirited and terribly altered appearance of the man who courted death in the whirlpool rapids of Niagara... let it be taken for granted that his object was not suicide, but money and imperishable fame.Webb rented a cottage and trained for a month at Nantasket Beach.

[1] The first part went smoothly, but upon being lifted by a large wave, Webb shouted and raised his arm, before being pulled underwater for about 130 ft (40 m).

[128][129] Rumours spread that Madeleine inherited a large sum, but Kyle told the public that Webb had left it to his children.

[136] In 1909, Webb's elder brother Thomas unveiled a memorial, funded by public donations, at the east end of Dawley High Street.