How many copies did Space Travel Idle sell?

14k to 23k copies, based on its 540 Steam reviews. This is a labeled estimate from the review count, not exact sales.

How much revenue did Space Travel Idle make?

Space Travel Idle is free to play, so there is no copy-sales revenue to estimate.

How big is Space Travel Idle?

Estimated owners: ≈ 14k–23k; from 540 reviews (Mixed)

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 Space Travel Idle out and predicted the genre from its 8 similar games. Every figure here, including Space Travel Idle's, is estimated from Steam reviews, not self-reported sales.

Copies, estimated from reviews

typical (middle half) 1.2M–2.3M

best case 8.2M (Slay the Spire)

The Card Battler genre

7 of your 8 similar games are hits. A big, proven genre for a game like yours.

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

A typical game

≈ 1.2M–2.3M copies

≈ $5.8M–$19.8M after Steam's cut

from ~50k reviews

Best case

≈ 6.2M–10.1M copies

Slay the Spire · ≈ $42.8M–$115.2M after Steam's cut

The genre you'd be entering

Your set: Your set clusters on Card Battler (3 of 8) and Card Game (3 of 8).
The winners: Winners here lead with Roguelike Deckbuilder + Card Game, priced around $25.
The era: The games you compared span 2019 to 2026, a genre with a long track record.

Copies and revenue are rough lifetime estimates from the review count.

Similar games

Game	Est. copies	Est. revenue	Price	Reviews	Tags
Minion Masters 2019	Est. copies ≈ 1.9M–3.1M SteamSpy 500k–1M	Est. revenue Free	Free	65k reviews Very Positive	PvETrading Card Game
KARDS - The WW2 Card Game 2020	Est. copies ≈ 1.3M–2.1M SteamSpy 2M–5M	Est. revenue Free	Free	50k reviews Mixed	Free to PlayCard Game
Library Of Ruina 2021	Est. copies ≈ 1.1M–1.8M SteamSpy 1M–2M	Est. revenue $8.9M–$24.1M after Steam's cut $16.3M–$37.0M before the cut	$29.99	44k reviews Very Positive	Story RichCard Game
觅长生 2023	Est. copies ≈ 760k–1.2M SteamSpy 1M–2M	Est. revenue $3.1M–$8.4M after Steam's cut $5.7M–$13.0M before the cut	$14.99	32k reviews Very Positive	RPGOpen World
Slay the Spire 2019	Est. copies ≈ 6.2M–10.1M 4.4x vs typical SteamSpy 5M–10M	Est. revenue $42.8M–$115.2M after Steam's cut $77.9M–$177.2M before the cut	$24.99	216k reviews Overwhelmingly Positive	Roguelike DeckbuilderCard Game
Stormworks: Build and Rescue 2020	Est. copies ≈ 1.6M–2.5M SteamSpy 1M–2M	Est. revenue $10.7M–$28.9M after Steam's cut $19.5M–$44.5M before the cut	$24.99	59k reviews Very Positive	SandboxBase-Building
Rogue Voltage 2026	Est. copies ≈ 15k–24k too small to compare SteamSpy under 20k	Est. revenue $66k–$178k after Steam's cut $121k–$274k before the cut	$15.99	628 reviews Very Positive	Early AccessDeckbuilding
Drunken Wrestlers 2 2019	Est. copies ≈ 538k–874k SteamSpy 500k–1M	Est. revenue $590k–$1.6M after Steam's cut $1.1M–$2.4M before the cut	$3.99	19k reviews Very Positive	Early AccessMultiplayer