Life Stages

Overview

Every Zoi in inZOI progresses through nine life stages, from Newborn to Senior, over the course of approximately 100 in-game days at default settings. Aging is automatic and cannot be paused through normal gameplay, although players can disable it entirely through the Simulation settings or by using cheats. Each stage has a fixed duration measured in in-game days, and the transition from one stage to the next happens instantly: one moment a Zoi is a Child, and the next they become an Adolescent with a different body, new abilities, and new gameplay options.

Additional Details

One in-game day lasts 96 real-world minutes by default. This can be adjusted in Game Options > Simulation through the Length of Day setting. The shortest option compresses a day into 48 real minutes; the longest stretches it to a full 24 real hours. At the default 96-minute day, a Zoi's full lifespan from Newborn to Senior death takes roughly 112 real-world hours of play (about 70 sessions at 90+ minutes each). At the fastest 48-minute setting, the same lifespan compresses to approximately 56 real-world hours.

Changing the day length speeds up or slows down how fast time passes but does not extend a Zoi's overall lifespan in terms of in-game days. Life stages interact with many other game systems, including skills, school attendance, careers, relationships, and death. The stage a Zoi occupies determines which of these systems are available to them.

All Nine Life Stages

The table below lists every life stage, its duration in in-game days, the cumulative day count from birth, the approximate equivalent age range, and whether the stage can be selected when creating a new Zoi in Create a Zoi.

The total lifespan adds up to roughly 82 to 100 in-game days depending on how long the Senior stage lasts. The Senior stage has built-in randomness, so no two Zois die at exactly the same age.

Character Creation Restrictions

When creating a new Zoi in Create a Zoi, players can choose from six of the nine stages: Child, Teenager, Young Adult, Adult, Middle-Aged, and Senior. The three remaining stages (Newborn, Toddler, and Adolescent) are only reachable through gameplay. Newborns and Toddlers can only exist when a Zoi is born through pregnancy, while the Adolescent stage is only reachable when a Child Zoi ages up naturally. The same restrictions apply when adding a Zoi to an existing household.

Newborns

The Newborn stage lasts just 1 in-game day and only occurs when a Zoi is born through pregnancy. The baby appears in a crib and cannot be directly controlled by the player. Parents handle feeding and basic care automatically. If both parents leave the lot, an auto-babysitter system kicks in to watch over the baby.

Newborns have a limited set of interactions. Parents and other household members can check the baby's temperature, talk to the baby, and show affection. The baby can laugh, cry, and have its diaper changed. Newborns are born without teeth and gain them as they grow. Their needs (hunger, hygiene, comfort) can trigger emotion buffs or cause them to wake nearby Zois if those needs become urgent.

As of the March 2026 anniversary update (v0.7.0), baby Zois received adjusted needs, can be customized in the Edit Appearance menu, and a new quick-cleanup interaction was added for caregivers.

Toddlers

The Toddler stage lasts 2 in-game days (cumulative 3 days from birth). Toddlers can walk, talk in fragments, and begin developing 4 foundational skills. They are more hands-on than Newborns: players must feed them formula, change their diapers, and manage their needs directly. Toddlers sleep on toddler rugs or mattresses that spawn on the ground rather than in regular beds.

Like Newborns, Toddlers cannot be selected in Create a Zoi. They are only reachable through natural aging from the Newborn stage.

Toddler Skills

Toddlers have 4 foundational skills, each capped at level 5. These skills lay the groundwork for related adult skills through the Aptitude system.

Maxing a toddler skill to level 5 before aging up gives the Zoi a meaningful head start on the related grown-up skill. The bonus applies automatically at the stage transition without any player input required.

Children

The Child stage lasts 7 in-game days (cumulative 10 days from birth) and covers ages roughly equivalent to 3 through 10 years old. Children attend elementary school from 9 AM to 2 PM, five days a week, and receive homework assignments. They can develop 6 child-specific skills and are the first stage selectable in Create a Zoi.

Children have a special protection system. If a child's needs become critically low, the Child Protection Agency intervenes and takes the child away from the household rather than letting them die. This protection applies to situations where the child is starving, freezing, or otherwise severely neglected. If both parents die, children are also sent to the Child Protection Agency. This safety net does not extend to Teenagers, who can die from the same causes as adults.

During the Child stage, Zois begin developing traits and can be assigned a trait through the trait selection system. Children can also perform self-care tasks, interact with toys, and build friendships with other Zois.

Child Skills

Children have 6 skills that are separate from the adult skill tree, each capped at level 5. When a child ages up to Teenager, maxed child skills provide a bonus to related adult skills through the Aptitude system. The child automatically starts with the related adult skill at level 5 if the child skill was maxed.

Creativity is the most valuable child skill to max because it transfers to four different adult skills simultaneously. A child who maxes Creativity before aging up starts their Teenager stage with level 5 in Performance, Media Production, Art, and Instrument. Motor Development feeds directly into Fitness. The Aquatic Adaptability and Curious Mind skills were added in the v0.3.0 update.

Adolescents

The Adolescent stage lasts 6 in-game days (cumulative 16 days from birth) and covers ages roughly equivalent to 11 through 15 years old. This stage serves as a bridge between childhood and the teenage years, and it is one of three stages that cannot be selected in Create a Zoi. The only way to reach the Adolescent stage is by having a Child Zoi age up naturally.

Adolescents attend middle school from 9 AM to 4 PM and continue to develop their skills. The inclusion of a dedicated Adolescent stage (separate from both Child and Teenager) is one of the features that distinguishes inZOI from other life simulation games. It provides a transitional period with middle school attendance and gradual development before the more independent Teenager stage begins.

Teenagers

The Teenager stage lasts 4.5 in-game days (cumulative about 20 days from birth) and covers ages roughly equivalent to 16 through 20 years old. Teenagers attend high school from 9 AM to 5 PM and gain access to a much wider range of gameplay features than Children and Adolescents.

Key unlocks at the Teenager stage include:

The Teenager stage is relatively short at only 4.5 days. Because child skills transfer their Aptitude bonuses at this transition, it is important to max as many child skills as possible before the Zoi ages into a Teenager.

Young Adults

The Young Adult stage lasts 9 in-game days (cumulative about 29.5 days from birth) and represents ages roughly equivalent to 20 through 30 years old. This is the first stage where Zois gain full access to all major life systems.

Key unlocks at the Young Adult stage include:

Adults

The Adult stage is the longest stage in the game, lasting 20 in-game days (cumulative about 49.5 days from birth). This represents ages roughly equivalent to 30 through 50 years old. Adults have access to everything Young Adults can do, plus expanded career progression opportunities. This is typically the stage where Zois reach the peak of their careers and build established families.

There are no new unique feature unlocks at the Adult stage compared to Young Adult. The extended duration gives players ample time to develop their Zoi's career, raise children, build wealth, and pursue long-term goals. At 20 days, the Adult stage alone accounts for roughly one-fifth of a Zoi's total lifespan.

Middle-Aged

The Middle-Aged stage lasts 16 in-game days (cumulative about 65.5 days from birth) and represents ages roughly equivalent to 50 through 65 years old. Like the Adult stage, there are no new unique feature unlocks. Zois continue their career and family life as normal.

Middle-Aged Zois may notice that their children have grown up and left the household. This stage is often where multi-generational family stories take shape, as the original Zoi watches their offspring progress through their own life stages.

Seniors

The Senior stage lasts approximately 17 in-game days, though the exact duration varies due to built-in randomness. This is the final stage of a Zoi's life, representing ages 65 and older. Retirement becomes available, and natural death from old age becomes possible.

As of v0.1.3 (April 1, 2025), only Zois in the Senior life stage can die naturally from old age. Before this patch, natural death could occur at any adult life stage based on probabilistic calculations. The developers changed this because, as they stated, "it's important for Creators to have time to bond with their characters and fully immerse themselves in their stories." This rule applies only to natural death from aging. Non-natural deaths (fire, drowning, electrocution, starvation, sleep deprivation, car accidents, falling) can still happen at any stage from Teenager onward.

The Senior stage is unpredictable. There is no warning or countdown before a Zoi dies of old age. Players should save frequently once a Zoi reaches this stage. When a Zoi dies, the player receives a "Go Back In Time" option to load a previous save.

Death and the Afterlife

When a Zoi dies (whether from old age or other causes), what happens next depends on their Karma score. Every action a Zoi performs throughout their life accumulates karma points, both positive and negative.

Surviving family members experience sadness and depression after a Zoi's death. If too many ghosts accumulate in a city, new Zois cannot be born and families cannot be created. Players must help ghosts resolve their karma to keep the city healthy. For full details on all death types and mechanics, see the Deaths article.

The Aging-Up Process

Zois do not age continuously or visibly day by day. They remain at one life stage for its full duration, then jump to the next stage instantly. When a Zoi ages up, their physical appearance (height, build, face) changes immediately to match the new stage. There is no visible progress bar or countdown showing how close a Zoi is to aging up. The transition happens automatically when the required number of in-game days has been reached.

Only the currently selected Zoi receives life stage transition notifications. Death notifications, however, appear regardless of which Zoi is selected. Child skills (Creativity, Motor Development, Social, Responsibility, Aquatic Adaptability, Curious Mind) transfer their Aptitude bonuses to adult skills when the Zoi ages into a Teenager.

Feature Unlocks by Life Stage

Each life stage unlocks new gameplay capabilities. The table below summarizes the key unlocks at each stage.

Simulation Speed and Day Length

Aging speed is controlled by settings found in Game Menu > Options > Simulation. These settings affect all time-based systems in the game, including aging, career schedules, school attendance, seasonal transitions, and need decay rates.

The ability to disable aging separately for your own Zois and city NPCs was introduced in v0.1.4 (the April 4, 2025 hotfix). Shorter days mean Zois age faster but also have less real time to complete daily activities like attending school, going to work, or socializing.

Aging Cheats

Players who want more direct control over aging can use the cheat console. To open it, first enable cheats through Psycat's Advice, then press Ctrl + Shift + C. The following aging-related cheats are available:

To find a Zoi's ID for these commands, use the showZoiInfo true cheat, which displays each Zoi's ID above their head.

Tips

• If you want a long-lived Zoi without disabling aging entirely, increase the Length of Day setting. Setting it to 24 hours per in-game day makes each life stage last many real-world days, giving you extensive time at each stage.

• Disable aging selectively: freeze aging for your household while letting city NPCs age normally. This keeps the world dynamic while giving you unlimited time with your main characters.

• Plan skill development around life stage durations. Children have 7 days to max their 6 child skills, and Teenagers have only 4.5 days before becoming Young Adults. Prioritize the most impactful skills first; Creativity is the best because it transfers to four adult skills.

• The Senior stage is unpredictable. Save frequently once a Zoi reaches Senior age, as death from old age can happen at any time without warning.

• If you want to experience the full lifecycle from Newborn to Senior death, start with a pregnant couple. The resulting child will age through every stage naturally, giving the most complete experience of all nine life stages.

• Use the AgeUP and AgeDOWN cheats to skip stages you find tedious, or to replay stages you enjoyed. These are especially useful for testing builds or experiencing specific content without waiting.

• If both parents of a Child die, the Child Protection Agency takes the children away. To avoid losing child Zois, make sure at least one adult is always available in the household, or use the immortalZoi cheat on the parents as a safety net.