Express quick Archer, 29, is currently playing white-ball cricket only but England hope to have the 2019 50-over World Cup winner, whose career has been blighted by injuries, back playing Test cricket next year.
He will continue to play for south coast side Sussex until the end of the 2025 season, in an arrangement that ties in with his current England and Wales Cricket Board central contract.
The 30-year-old fast-medium Robinson, who lost his England place earlier this season and made unwanted headlines when hit for a record 43 runs in an over by Leicestershire's Louis Kimber last month, is also staying at Hove.
"I am delighted that both Jofra and Oliver have extended their contracts with the club for another year," said Sussex head coach Paul Farbrace.
"It is fantastic to see Jofra back playing and being able to enjoy his high level of skill on the field.
"He has made a significant contribution to club, even when he has not been able to play.
"Oliver has played a key role for the team this season in both the County Championship and the (T20) Blast and he has contributed hugely to the on-field progress we have made as a club."