I saw that some people don't know how long some of the races live in Monsters Of The Multiverse because they aren't stated directly in the race's description, so I'm here to list the lifespans of all the races in that book. Sadly they do not state when the races reach maturity/adulthood so you'll have to go off older 5e material for that.
Page 6 of Monsters Of The Multiverse:
"Life Span"
"The typical life span of a player character in the D&D multiverse is about a century, assuming the character doesn't meet a violent end on an adventure. Members of some races, such as dwarves and elves, can live for centuries. If typical members of a race in this book can live longer than a century, that fact is mentioned in the race's description."
This means that all playable races in the book live for a century unless stated in the race's description.
Lifespans of races:
Aararakocra- 100yrs (unstated in its description on page 6 so refer to "Life Span" on page 6)
Aasimar- 160yrs (page 7)
Bugbear- 100yrs (unstated on page 8 so refer to page 6)
Centaur- 100yrs (unstated on page 9 so refer to page 6)
Changeling- 100yrs (unstated on page 10 so refer to page 6)
Deep Gnome- 500yrs (page 11)
Duergar- 350yrs (page 12)
Eladrin- over 750yrs (page 13)
Fairy- 100yrs (page 14)
Firbolg- 500yrs (page 15)
Genasi- 120yrs (page 16)
Githyanki- outside the Astral Plane they live for 100yrs but can live indefinitely in the Astral Plane (page 18)
Githzerai- 100yrs (unstated on page 19 so refer to page 6)
Goblin- 100yrs (unstated on page 20 so refer to page 6)
Goliath- 100yrs (unstated on page 21 so refer to page 6)
Harengon- 100yrs (unstated on page 22 so refer to page 6)
Hobgoblin- 100yrs (unstated on page 23 so refer to page 6)
Kenku- 100yrs (unstated on page 24 so refer to page 6)
Kobold- 100yrs (unstated on page 25 so refer to page 6)
Lizardfolk- 100yrs (unstated on page 26 so refer to page 6)
Minotaur- 100yrs (unstated on page 27 so refer to page 6)
Orc- 100yrs (unstated on page 28 so refer to page 6)
Satyr- 100yrs (unstated on page 29 so refer to page 6)
Sea Elf- over 750yrs (page 30)
Shadar-Kai- over 750yrs (page 31)
Shifter- 100yrs (unstated on page 32 so refer to page 6)
Tabaxi- 100yrs (unstated on page 33 so refer to page 6)
Tortle- 100yrs (unstated on page 34 so refer to page 6)
Triton- 100yrs (unstated on page 35 so refer to page 6)
Yuan-Ti- 100yrs (unstated on page 36 so refer to page 6)
Just to add to this in case anyone is interested. Some of the original sources for these races have additional information on ages. I also added the PHB races and some of the others for interest.
The 100 year baseline seems to be part of the trend to getting away from "bias" in a fantasy game and allowing the players to choose how old their character is, unconstrained by typical members of the species. MMoM seems to have removed all references that were less that a century and some of those that were over a century.
(V) = Volos, (E) = Eberron, (PHB) = Players Handbook, (EEPC) = Elemental Evil Players Companion, (MOT) = Mythic Odysseys of Theros, (MToF) = Mordenkainen's Tome of Foes
Lifespans of races:
Aararakocra- Aarakocra reach maturity by age 3. Compared to humans, aarakocra don’t usually live longer than 30 years. (EEPC)
Aasimar- Aasimar mature at the same rate as humans, but they can live up to 160 years. (V)
Bugbear- Bugbears reach adulthood at age 16 and live up to 80 years.(V)
Centaur- Centaurs mature and age at about the same rate as humans. (MOoT)
Changeling- Changelings mature slightly faster than humans but share a similar lifespan — typically a century or less. While a changeling can transform to conceal their age, the effects of aging affect them similarly to humans. (E)
Deep Gnome- Deep gnomes are short-lived for gnomes. They mature at the same rate humans do and are considered full-grown adults by 25. They live 200 to 250 years, although hard toil and the dangers of the Underdark often claim them before their time. (EEPC)
Duergar- see Dwarf - 350yrs (page 12)
Dragonborn - Young dragonborn grow quickly. They walk hours after hatching, attain the size and development of a 10-year-old human child by the age of 3, and reach adulthood by 15. They live to be around 80. (PHB) (Fizbans doesn't seem to include an age entry)
Dwarf - Dwarves mature at the same rate as humans, but they’re considered young until they reach the age of 50. On average, they live about 350 years. (PHB)
Eladrin- see Elf - over 750yrs (page 13)
Elf - Although elves reach physical maturity at about the same age as humans, the elven understanding of adulthood goes beyond physical growth to encompass worldly experience. An elf typically claims adulthood and an adult name around the age of 100 and can live to be 750 years old. (PHB) (applies to all variations - shadar-kai, eladrin, etc)
Fairy- 100yrs (page 14) (WBW - also says about a century)
Firbolg- As humanoids related to the fey, firbolg have long lifespans. A firbolg reaches adulthood around 30, and the oldest of them can live for 500 years. (V)
Genasi- Genasi mature at about the same rate as humans and reach adulthood in their late teens. They live somewhat longer than humans do, up to 120 years. (EEPC)
Githyanki- Gith reach adulthood in their late teens and live for about a century. (MToF) - does not seem to contain the additional information found in MMoM -> outside the Astral Plane they live for 100yrs but can live indefinitely in the Astral Plane (page 18)
Githzerai- Gith reach adulthood in their late teens and live for about a century. (MToF)
Gnome - Gnomes mature at the same rate humans do, and most are expected to settle down into an adult life by around age 40. They can live 350 to almost 500 years. (PHB)
Goblin- Goblins reach adulthood at age 8 an d live up to 60 years. (V)
Goliath - Goliaths have life spans comparable to humans. They enter adulthood in their late teens and usually live less than a century. (V)
Half-elf - Half-elves mature at the same rate humans do and reach adulthood around the age of 20. They live much longer than humans, however, often exceeding 180 years. (PHB)
Halfling - A halfling reaches adulthood at the age of 20 and generally lives into the middle of his or her second century. (PHB)
Half-orc - Half-orcs mature a little faster than humans, reaching adulthood around age 14. They age noticeably faster and rarely live longer than 75 years. (PHB)
Harengon- 100yrs (unstated on page 22 so refer to page 6) (WBW - also says about a century)
Hobgoblin- Hobgoblins mature at the same rate as humans and have lifespans similar in length to theirs. (V)
Human - Humans reach adulthood in their late teens and live less than a century. (PHB)
Kalashtar - Kalashtar mature and age at the same rate as humans. (E)
Kenku- Kenku have shorter lifespans than humans. They reach maturity at about 12 years old and can live to 60. (V)
Kobold- Kobolds reach adulthood at age 6 and can live up to 120 years but rarely do so. (V)
Lizardfolk- Lizardfolk reach maturity around age 14 and rarely live longer than 60 years.(V)
Locathah - Locathah mature to adulthood by the age of 10 but have been known to live up to 80 years. (extra life - locathah supplement)
Minotaur- Minotaurs mature and age at about the same rate as humans. (MOT)
Orc- Orcs reach adulthood at age 12 and live up to 50 years. (V)
Satyr- Satyrs mature and age at about the same rate as humans. (MOT)
Sea Elf- see Elf - over 750yrs (page 30)
Shadar-Kai- see Elf - over 750yrs (page 31)
Shifter- Shifters are quick to mature both physically and emotionally, reaching young adulthood at age 10. They rarely live to be more than 70 years old. (E)
Tabaxi- Tabaxi have lifespans equivalent to humans.(V)
Tiefling - Tieflings mature at the same rate as humans but live a few years longer.(PHB)
Tortle-Young tortles crawl for a few weeks after birth before learning to walk on two legs. They reach adulthood by the age of 15 and live an average of 50 years. (Tortle Package)
Triton- Tritons reach maturity around age 15 and can live up to 200 years. (V) (MOT)
Warforged - A typical warforged is between two and thirty years old. The maximum warforged lifespan remains a mystery; so far, warforged have shown no signs of deterioration due to age. You are immune to magical aging effects. (E)
Yuan-Ti- Purebloods mature at the same rate as humans and have lifespans similar in length to theirs.(V)
I saw that some people don't know how long some of the races live in Monsters Of The Multiverse because they aren't stated directly in the race's description, so I'm here to list the lifespans of all the races in that book. Sadly they do not state when the races reach maturity/adulthood so you'll have to go off older 5e material for that.
Page 6 of Monsters Of The Multiverse:
"Life Span"
"The typical life span of a player character in the D&D multiverse is about a century, assuming the character doesn't meet a violent end on an adventure. Members of some races, such as dwarves and elves, can live for centuries. If typical members of a race in this book can live longer than a century, that fact is mentioned in the race's description."
This means that all playable races in the book live for a century unless stated in the race's description.
Lifespans of races:
Aararakocra- 100yrs (unstated in its description on page 6 so refer to "Life Span" on page 6)
Aasimar- 160yrs (page 7)
Bugbear- 100yrs (unstated on page 8 so refer to page 6)
Centaur- 100yrs (unstated on page 9 so refer to page 6)
Changeling- 100yrs (unstated on page 10 so refer to page 6)
Deep Gnome- 500yrs (page 11)
Duergar- 350yrs (page 12)
Eladrin- over 750yrs (page 13)
Fairy- 100yrs (page 14)
Firbolg- 500yrs (page 15)
Genasi- 120yrs (page 16)
Githyanki- outside the Astral Plane they live for 100yrs but can live indefinitely in the Astral Plane (page 18)
Githzerai- 100yrs (unstated on page 19 so refer to page 6)
Goblin- 100yrs (unstated on page 20 so refer to page 6)
Goliath- 100yrs (unstated on page 21 so refer to page 6)
Harengon- 100yrs (unstated on page 22 so refer to page 6)
Hobgoblin- 100yrs (unstated on page 23 so refer to page 6)
Kenku- 100yrs (unstated on page 24 so refer to page 6)
Kobold- 100yrs (unstated on page 25 so refer to page 6)
Lizardfolk- 100yrs (unstated on page 26 so refer to page 6)
Minotaur- 100yrs (unstated on page 27 so refer to page 6)
Orc- 100yrs (unstated on page 28 so refer to page 6)
Satyr- 100yrs (unstated on page 29 so refer to page 6)
Sea Elf- over 750yrs (page 30)
Shadar-Kai- over 750yrs (page 31)
Shifter- 100yrs (unstated on page 32 so refer to page 6)
Tabaxi- 100yrs (unstated on page 33 so refer to page 6)
Tortle- 100yrs (unstated on page 34 so refer to page 6)
Triton- 100yrs (unstated on page 35 so refer to page 6)
Yuan-Ti- 100yrs (unstated on page 36 so refer to page 6)
Just to add to this in case anyone is interested. Some of the original sources for these races have additional information on ages. I also added the PHB races and some of the others for interest.
The 100 year baseline seems to be part of the trend to getting away from "bias" in a fantasy game and allowing the players to choose how old their character is, unconstrained by typical members of the species. MMoM seems to have removed all references that were less that a century and some of those that were over a century.
(V) = Volos, (E) = Eberron, (PHB) = Players Handbook, (EEPC) = Elemental Evil Players Companion, (MOT) = Mythic Odysseys of Theros, (MToF) = Mordenkainen's Tome of Foes
Lifespans of races:
Aararakocra- Aarakocra reach maturity by age 3. Compared to humans, aarakocra don’t usually live longer than 30 years. (EEPC)
Aasimar- Aasimar mature at the same rate as humans, but they can live up to 160 years. (V)
Bugbear- Bugbears reach adulthood at age 16 and live up to 80 years.(V)
Centaur- Centaurs mature and age at about the same rate as humans. (MOoT)
Changeling- Changelings mature slightly faster than humans but share a similar lifespan — typically a century or less. While a changeling can transform to conceal their age, the effects of aging affect them similarly to humans. (E)
Deep Gnome- Deep gnomes are short-lived for gnomes. They mature at the same rate humans do and are considered full-grown adults by 25. They live 200 to 250 years, although hard toil and the dangers of the Underdark often claim them before their time. (EEPC)
Duergar- see Dwarf - 350yrs (page 12)
Dragonborn - Young dragonborn grow quickly. They walk hours after hatching, attain the size and development of a 10-year-old human child by the age of 3, and reach adulthood by 15. They live to be around 80. (PHB) (Fizbans doesn't seem to include an age entry)
Dwarf - Dwarves mature at the same rate as humans, but they’re considered young until they reach the age of 50. On average, they live about 350 years. (PHB)
Eladrin- see Elf - over 750yrs (page 13)
Elf - Although elves reach physical maturity at about the same age as humans, the elven understanding of adulthood goes beyond physical growth to encompass worldly experience. An elf typically claims adulthood and an adult name around the age of 100 and can live to be 750 years old. (PHB) (applies to all variations - shadar-kai, eladrin, etc)
Fairy- 100yrs (page 14) (WBW - also says about a century)
Firbolg- As humanoids related to the fey, firbolg have long lifespans. A firbolg reaches adulthood around 30, and the oldest of them can live for 500 years. (V)
Genasi- Genasi mature at about the same rate as humans and reach adulthood in their late teens. They live somewhat longer than humans do, up to 120 years. (EEPC)
Githyanki- Gith reach adulthood in their late teens and live for about a century. (MToF) - does not seem to contain the additional information found in MMoM -> outside the Astral Plane they live for 100yrs but can live indefinitely in the Astral Plane (page 18)
Githzerai- Gith reach adulthood in their late teens and live for about a century. (MToF)
Gnome - Gnomes mature at the same rate humans do, and most are expected to settle down into an adult life by around age 40. They can live 350 to almost 500 years. (PHB)
Goblin- Goblins reach adulthood at age 8 an d live up to 60 years. (V)
Goliath - Goliaths have life spans comparable to humans. They enter adulthood in their late teens and usually live less than a century. (V)
Half-elf - Half-elves mature at the same rate humans do and reach adulthood around the age of 20. They live much longer than humans, however, often exceeding 180 years. (PHB)
Halfling - A halfling reaches adulthood at the age of 20 and generally lives into the middle of his or her second century. (PHB)
Half-orc - Half-orcs mature a little faster than humans, reaching adulthood around age 14. They age noticeably faster and rarely live longer than 75 years. (PHB)
Harengon- 100yrs (unstated on page 22 so refer to page 6) (WBW - also says about a century)
Hobgoblin- Hobgoblins mature at the same rate as humans and have lifespans similar in length to theirs. (V)
Human - Humans reach adulthood in their late teens and live less than a century. (PHB)
Kalashtar - Kalashtar mature and age at the same rate as humans. (E)
Kenku- Kenku have shorter lifespans than humans. They reach maturity at about 12 years old and can live to 60. (V)
Kobold- Kobolds reach adulthood at age 6 and can live up to 120 years but rarely do so. (V)
Lizardfolk- Lizardfolk reach maturity around age 14 and rarely live longer than 60 years.(V)
Locathah - Locathah mature to adulthood by the age of 10 but have been known to live up to 80 years. (extra life - locathah supplement)
Minotaur- Minotaurs mature and age at about the same rate as humans. (MOT)
Orc- Orcs reach adulthood at age 12 and live up to 50 years. (V)
Satyr- Satyrs mature and age at about the same rate as humans. (MOT)
Sea Elf- see Elf - over 750yrs (page 30)
Shadar-Kai- see Elf - over 750yrs (page 31)
Shifter- Shifters are quick to mature both physically and emotionally, reaching young adulthood at age 10. They rarely live to be more than 70 years old. (E)
Tabaxi- Tabaxi have lifespans equivalent to humans.(V)
Tiefling - Tieflings mature at the same rate as humans but live a few years longer.(PHB)
Tortle- Young tortles crawl for a few weeks after birth before learning to walk on two legs. They reach adulthood by the age of 15 and live an average of 50 years. (Tortle Package)
Triton- Tritons reach maturity around age 15 and can live up to 200 years. (V) (MOT)
Warforged - A typical warforged is between two and thirty years old. The maximum warforged lifespan remains a mystery; so far, warforged have shown no signs of deterioration due to age. You are immune to magical aging effects. (E)
Yuan-Ti- Purebloods mature at the same rate as humans and have lifespans similar in length to theirs.(V)
Great source. Thanks