How many copies did Endless Sky sell?

346k to 562k copies, based on its 7k Steam reviews. This is a labeled estimate from the review count, not exact sales.

How much revenue did Endless Sky make?

Endless Sky is free to play, so there is no copy-sales revenue to estimate.

How big is Endless Sky?

Estimated owners: ≈ 346k–562k; from 7k reviews (Very Positive)

A labeled estimate from the public review count (adjusted for release year), not exact sales. Owner data cross-checked with SteamSpy.

Does this actually work?

We left Endless Sky out and predicted the genre from its 8 similar games. Every figure here, including Endless Sky's, is estimated from Steam reviews, not self-reported sales.

Copies, estimated from reviews

typical (middle half) 3.9M–8.0M

best case 25.0M (Destiny 2)

Games like Endless Sky

The middle of these games

≈ 3.9M–8.0M copies

≈ $50.4M–$151.5M after Steam's cut

from ~139k reviews

Only the top fifth of 2019’s Steam releases earned about $34k gross, so plan for that or less.

All 8 of your similar games are hits.

Best case: Destiny 2 at ≈ 19.1M–31.0M copies. A breakout hit, far above a typical game.

What it took to get here

About half the games that made it here had over 11k reviews in their first month; the spread ran 7k to 96k.

The genre you'd be entering

Your set: Your set clusters on Open World (6 of 8) and Base-Building (3 of 8).
The winners: Winners here lead with Open World + Looter Shooter. The breakout hits carry Looter Shooter + PvE + MMORPG; a typical game here doesn't.
The era: The games you compared span 2012 to 2021, and none of them shipped in the last two years.

How these numbers were worked out

A hit here: 1,000+ reviews, roughly $150k+ before Steam's cut (a standard indie benchmark).

Copies come from each game's reviews times a sales-per-review rate that falls with release age, from about 31 for the most recent game here to about 79 for the oldest, then widened into a range; revenue rides on that estimate times price. Source: GameDiscoverCo (2020) and VG Insights (2021).

Similar games

Game	Est. copies	Est. revenue	Price	Reviews	Tags
Stormworks: Build and Rescue 2020	Est. copies ≈ 1.5M–2.4M SteamSpy 1M–2M	Est. revenue $10.2M–$27.4M after Steam's cut $18.5M–$42.2M before the cut	$24.99	60k reviews Very Positive	SandboxBase-Building
RimWorld 2018	Est. copies ≈ 7.5M–12.2M 1.8x vs typical SteamSpy 5M–10M	Est. revenue $72.0M–$193.5M after Steam's cut $130.8M–$297.7M before the cut	$34.99	246k reviews Overwhelmingly Positive	Colony SimBase-Building
ASTRONEER 2019	Est. copies ≈ 4.0M–6.5M SteamSpy 2M–5M	Est. revenue $33.0M–$88.8M after Steam's cut $60.1M–$136.6M before the cut	$29.99	139k reviews Very Positive	MultiplayerOpen World
Stellaris 2016	Est. copies ≈ 8.2M–13.3M SteamSpy 2M–5M	Est. revenue $112.7M–$303.1M after Steam's cut $205.0M–$466.3M before the cut	$49.99	197k reviews Very Positive	SpaceGrand Strategy
Destiny 2 2019	Est. copies ≈ 19.1M–31.0M 4.8x vs typical SteamSpy 20M–50M	Est. revenue Free	Free	662k reviews Mostly Positive	Free to PlayOpen World
PlanetSide 2 2012	Est. copies ≈ 4.7M–7.7M SteamSpy 5M–10M	Est. revenue Free	Free	75k reviews Very Positive	Free to PlayFPS
STAR WARS™: The Old Republic™ 2020	Est. copies ≈ 1.9M–3.0M SteamSpy 5M–10M	Est. revenue Free	Free	75k reviews Very Positive	Free to PlayMultiplayer
Halo Infinite 2021	Est. copies ≈ 4.5M–7.3M SteamSpy 10M–20M	Est. revenue Free	Free	181k reviews Mixed	Free to PlayFPS