A spider’s life is not four neat stages but an unbroken series of molts. This page names five checkpoints along that series: egg, spiderling, juvenile instars, subadult, and adult. How many molts fall between hatching and maturity varies by species, and no source checked here publishes one number for spiders as a group, unlike the four-stage egg-larva-pupa-adult diagram built for insects, which does not describe spider development at all. This reference on this site’s broader look at pest life cycles works through each checkpoint, a species-by-species timing table, and an egg sac calendar; use the headings below to jump to any stage.
Spider Life Cycle Stages, From Egg Sac to Adult
A spiderling hatches already built like a tiny adult: eight legs, a head region and abdomen, no wings to grow in later. That marks the core structural difference from the insect side of this site’s plant growth stages material: a caterpillar becomes a moth by way of a larva and a pupa, two stages a spider never has. A spider instead grows only by shedding its exoskeleton, checkpoint by checkpoint: egg (inside the sac), spiderling (newly hatched), juvenile instars (a series of molts, each a numbered instar), subadult (the final immature instar), and adult (sexually mature, and for many species and most males, done growing for good). The molt count inside “juvenile instars” is what differs most by species, covered next.
How Long Does It Take Spider Eggs to Hatch?
No source checked for this page gives an exact day count to hatching for any species, only the season it happens in. The Missouri Department of Conservation records two outdoor patterns pointing to an overwintering egg stage rather than a fast summer hatch: black-and-yellow garden spiders lay egg cases through summer and spiderlings do not emerge until the following spring, and grass spiders (funnel weavers) show the same shape, egg cases made through the season, overwintering, then hatching in spring. For these species the egg stage spans months, not days. House spiders are not tied to that outdoor calendar at all: a female can produce more than 15 sacs across her lifetime rather than one seasonal batch, consistent with the stable, climate-controlled setting she lives in.
How Many Times Does a Spider Molt Before Adulthood?
No source checked for this page publishes a general “spiders molt N times” figure, and Data Asset B below, molt count and maturity time by common spider type, leaves those cells empty rather than estimating. The indirect evidence is that the number varies widely: a species living three decades, like the tarantula female below, almost certainly molts more times than one finishing inside a single growing season.
Tarantulas are the one row where extension programs publish maturity timing, and they disagree roughly sevenfold. Colorado State University Extension, on Aphonopelma spp., estimates “males mature in about 7-10 years after egg hatch,” females needing “an additional 1-2 years.” LSU AgCenter, on Aphonopelma hentzi, says reaching adulthood “typically requires a year.” Neither cites the other, so read CSU’s as a genus-level Colorado estimate and LSU’s as one sentence on one species. CSU adds what both miss: these spiders “may molt more than once per year” early on, then molting “becomes an annual event.”
Spider Lifespan by Species
| Common spider type | Egg-to-hatch time | Instars before maturity | Time to adulthood | Typical adult lifespan |
|---|---|---|---|---|
| House spider (Parasteatoda tepidariorum) | Not published | Not published | Not published | 1+ year indoors; most temperate outdoor spiders live about 1 year (MDC) |
| Wolf spider (Lycosidae) | Not published | Not published | Not published | Some individuals survive nearly 2 years (MDC) |
| Jumping spider (bold jumper, Phidippus audax) | Not published; cocooned through summer, can overwinter unhatched | Not published | Not published | Not published; eggs, young, and adults can all overwinter (MDC) |
| Orb-weaver (garden spider, Argiope aurantia) | Not published; sac laid in summer, hatches the following spring | Not published | Matures and breeds within the growing season it hatches (MDC) | About 1 growing season; female dies at first frost |
| Funnel weaver (grass spider, Agelenidae) | Not published; overwinters as an egg, hatches in spring | Not published | Matures within the growing season it hatches (MDC) | About 1 growing season; dies at first freeze |
| Tarantula (Texas brown tarantula) | About 50 to 60 days (CSU, Aphonopelma spp.); young then stay with mother about a week (MDC) | Not published; molting goes from more than yearly to annual near maturity (CSU) | Sources disagree, see below: 7 to 10 years for males (CSU) against about 1 year (LSU AgCenter) | Females 30+ years; males around 7 years, often close to 1 year past maturity in the wild |
| Cellar spider (Pholcidae) | Not published | Not published | Not published | Not published |
Sources: MDC Discover Nature Field Guide, plus CSU Extension and LSU AgCenter where a row names them.
How Long Do Spiders Live, Egg to Adult to Death?
Lifespan is the widest documented spread on this page. The Missouri Department of Conservation states plainly that most spiders in Missouri’s temperate climate survive only a single year, dying with the first hard freeze, a pattern matched by its grass spider and garden spider profiles above. Indoors, the picture changes: a house spider in a climate-controlled building “may survive for more than a year,” per the same source. Wolf spiders push further, some individuals surviving nearly two years. The extreme case is the tarantula: MDC records females living more than 30 years and males around 7, though wild males often live barely a year past maturity.
Spider Egg Sac Timing, Season by Season
Outdoor annual species and the indoor house spider run on two different calendars. Garden spiders build roughly four egg cases across a female’s life, all made during summer, each holding more than 1,000 eggs; she dies at the first frost while her sacs overwinter and open the following spring (MDC). Grass spiders follow the same shape: cases made through the season, overwintering, then hatching in spring. Bold jumping spiders lay eggs in silken cocoons through summer, but uniquely, MDC notes eggs, young, and adults can all overwinter, so the calendar is not fixed to one stage. House spiders sit outside this rhythm, producing sacs on an ongoing basis. Tarantula females guard the egg case in a burrow until it hatches, young staying about a week before dispersing; MDC places the species’ most visible activity, wandering mature males, in late summer and fall.
House Spiders vs Outdoor Spiders, What Changes in the Timeline
Indoor conditions remove the boom-and-bust annual cycle outdoor species run on. A house spider’s stable setting supports ongoing egg-laying and a lifespan that can exceed a year, while an outdoor annual species like a garden or grass spider completes its entire life, egg to death, inside roughly one growing season, gated by the first hard freeze. One assumption is worth correcting here: wolf spiders are not part of the indoor house spider group. Burke Museum’s Spider Myths series, from its arachnology curator Rod Crawford, states that in North America no wolf spider (family Lycosidae) is part of the house spider fauna, that the family is identified by eye arrangement rather than size or hairiness, and that while some wander indoors, they do not survive there. The large spiders often mistaken for wolf spiders indoors are usually male European house spiders (Tegenaria/Eratigena) instead.
Spider Activity Timing by US Region, When You See the Most Spiders
No university or state program checked for this page publishes a region-by-region spider activity grid, so Data Asset A below is organized by species instead, drawing on the same MDC profiles used in Data Asset B above. One assumption is worth flagging first: Burke Museum’s Rod Crawford documents that late summer, the season most people call “spider season,” is actually one of the weaker times of year for spider numbers overall, since only a few large species mature then; fall and spring ran ahead of summer in the region he studied. Separately, the University of California Statewide IPM Program notes homes see more wandering spiders in mating season, when mature wolf spider and tarantula males search for females and some end up indoors by accident, a behavior detail distinct from population abundance.
Spider Activity by Season
| Common spider type | Egg sac appearance window | Peak sighting period | Typical overwintering stage |
|---|---|---|---|
| House spider (indoor) | Ongoing; a female produces 15+ sacs over her life | Not seasonal; indoor conditions stay stable year-round | Not applicable outdoors; indoor adults may persist a second year |
| Wolf spider | Not published | Outdoor, ground level; per Burke Museum, not part of the indoor fauna | Not stated; the nearly-2-year lifespan implies some overwinter past year 1 |
| Jumping spider (bold jumper) | Summer, in silken cocoons in crevices | Not published | Egg, young, or adult; MDC states all three can overwinter |
| Orb-weaver (garden spider) | Summer, about 4 cases per female | Females visible all summer; spiderlings visible after spring dispersal | Egg, inside the sac (overwintering cases eaten by birds, per MDC) |
| Funnel weaver (grass spider) | Through the growing season | Webs conspicuous, summer into fall | Egg, inside an overwintering sac |
| Tarantula | Not published | Late summer and fall, wandering mature males | Not applicable annually; individuals persist for years |
Sources: Missouri Department of Conservation, Discover Nature Field Guide, species pages named in each row; Burke Museum Spider Myths (Rod Crawford); University of California Statewide IPM Program, Spider Management Guidelines.
What ‘Instar’ Means in a Spider’s Molting Timeline
This pillar’s life-cycles hub defines an instar in general terms as the form a growing arthropod takes between two consecutive molts. For a spider, there is no larva and no pupa to distinguish from a nymph, the insect-only distinction the hub’s terminology table covers; a spiderling is already the adult body plan in miniature from the moment it hatches, so every instar between hatching and maturity is simply a larger, sometimes differently patterned, version of the one before it. Growth happens only at a molt, since the exoskeleton cannot expand on its own between molts. The last instar before the maturing molt is called the subadult; once that final molt happens, most male spiders stop growing and molting for good, while the pattern for females varies by species (see the FAQ below on molting after maturity).
Why Do Some Spider Egg Sacs Never Hatch?
The one documented cause found across the sources checked for this page is predation. The Missouri Department of Conservation records that the large, overwintering egg cases of the black-and-yellow garden spider are eaten by birds such as titmice and chickadees during winter, so some sacs never reach spring intact regardless of how or where they were built. Other explanations repeated elsewhere, such as extreme cold or a sac drying out, were not confirmed by a named source checked here, so they are not asserted as documented fact. What the sourced material does establish is that an overwintering sac faces real predation pressure for months, not days, part of why not every sac a female produces yields spiderlings the following spring.
Molting, Shedding, or Instars, Different Words for the Same Stage
Readers search this idea several ways, and all point at the same event: an exoskeleton being shed so the spider underneath can expand. This pillar’s life-cycles hub already sorts “instar” from related insect terms like larva and nymph in its own terminology table; that table is scoped to insects and is not repeated here. What is spider-specific is the mechanics: the discarded exoskeleton, sometimes called a molt or cast skin, keeps its shape closely enough to be mistaken for a dead spider. MDC’s house spider profile shows how loosely the vocabulary travels, noting the spider “cuts loose the dry, drained insect shell and lets it fall to the ground below the web” after a meal, a different event (feeding) from the spider’s own molt, though casual use blurs the two.
Do All Spiders Really Live Only One Year?
The “spiders only live a year” line comes from a real pattern, just not a universal one. It holds for outdoor annual species facing a hard freeze: MDC states garden spider females die at the first frost, and grass spiders “generally die when it freezes.” It does not hold for the indoor and long-lived species in the lifespan spread above, which run on a different clock entirely. The rule is not really about spiders as a group, then. It is about whether a given spider meets a freeze.
What Happens to Spiderlings After They Leave the Egg Sac?
Dispersal timing differs by species. Garden spider spiderlings emerge from the overwintered sac in spring and disperse by ballooning, riding strands of silk on the breeze, a natural developmental transition. House spider hatchlings take a slower path, often staying in the mother’s web several days before dispersing. Wolf spider spiderlings stay closest to the mother: after emerging from the sac she carries, they climb onto her abdomen and remain there up to two weeks or more before independence. Tarantula young stay with the mother in the burrow about a week after hatching before dispersing.
Frequently Asked Questions
How many eggs are in a typical spider egg sac? It varies by family. MDC records 100 to 400 eggs per sac for the common house spider, versus more than 1,000 per case for the black-and-yellow garden spider. No single figure applies across spiders as a group.
Do spiders molt after they reach adulthood? Some do. Colorado State University Extension records female tarantulas molting after maturity, “shortly after the young have left the burrow,” usually late July or early August. No source checked here gives a rule covering spiders generally.
What is the difference between an egg sac and a cocoon? MDC pages use both terms without a fixed rule: bold jumping spider eggs are called a cocoon, garden spider and house spider eggs are called sacs, and cellar spiders carry a loose, unbound egg cluster in their jaws instead.
How long can an unhatched spider egg sac sit before it fails? No source checked here publishes a duration figure. What is documented is a failure cause, not a countdown: see the section above on egg sacs that never hatch.
Do all spider species follow the same number of life stages? The broad checkpoint sequence, egg, spiderling, juvenile instars, subadult, adult, is shared. The molt count inside it is not published as one figure for spiders.
See also the flea life cycle from egg to adult, when flea populations peak indoors, and how long a jumping spider actually lives.
Sources
Missouri Department of Conservation, Discover Nature Field Guide, species profiles: Wolf Spiders, Common House Spider, Cellar Spiders, Black and Yellow Garden Spider, Grass Spiders, Bold Jumper, Texas Brown Tarantula.
Burke Museum, Spider Myths (Rod Crawford): Late Summer Has the Most Spiders, Wolf Spiders Live Indoors.
University of California Statewide IPM Program, Spider Management Guidelines.
Colorado State University Extension, Colorado Arachnids of Interest: Tarantulas (Aphonopelma spp.).
LSU AgCenter, Aphonopelma hentzi, The Louisiana Tarantula.
Related on this site: the pantry moth’s four stages works through a household insect whose stages are told apart by where each one sits in a room rather than by how it looks.
Last verified: 2026-08-16, against the MDC field guide pages, Burke Museum pages, UC IPM page, and the CSU Extension and LSU AgCenter tarantula fact sheets above.