SunLicensePremium Minecraft mods, one key per player.
Free build on Modrinth, Premium unlocked by a key per player.
Free plan · No credit card · Set up in minutes
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Java- Fabric
- NeoForge
- Modrinth
- CurseForge
- BuiltByBit
- Voxel Shop
- Gumroad
- Ko-fi
- Discord
Built for how you sell.
A key per purchase
In the jar, or on the receipt.
Two PCs, not twenty
A shared key stops at the third PC.
TOO_MANY_MACHINESRefunds turn Premium off
Voxel Shop, Gumroad and Stripe refunds revoke keys.
Free here, Premium there
Free on Modrinth, Premium sold where allowed.
A Premium Discord role
Comes off when the key is revoked.
Keeps working offline
A signed license file verifies offline.
Ed25519Live before your next release.
- 1Create a free account
- 2Connect BuiltByBit or Gumroad
- 3Add the Java SDK
public final class MyModClient implements ClientModInitializer {
static volatile boolean premium;
@Override
public void onInitializeClient() {
SunLicense sl = new SunLicense.Builder()
.baseUrl("https://api.sunlicense.com")
.token(Build.API_KEY) // validate-only slk_ key
.build();
String key = Config.licenseKey(); // AX8P-XXXX-XXXX-XXXX
String pc = Config.deviceId(); // random id in config/
// off the render thread; Premium stays off until it says yes
CompletableFuture.runAsync(() -> premium =
sl.validate(key, Map.of("host", pc)).isValid());
}
}Questions, answered.
Can a mod on Modrinth or CurseForge use license keys?
Modrinth and CurseForge are for free downloads. Modrinth doesn't ban license checks, but network calls must be disclosed on the project page. On CurseForge some games forbid monetised mods outright, so check the game's rules first. The usual setup is a fully working free build there and Premium sold on BuiltByBit, Voxel Shop or Gumroad.
How does a Fabric or Forge client mod check its license?
Bundle the SunLicense Java SDK in your mod jar, read the key from your config file and call validate with a random device ID you store in the config folder. Run it off the render thread at start-up and again every few hours, and keep Premium features off until it says yes. Our Fabric template on GitHub shows the whole pattern; it is a server mod, and the same check works in a client initializer.
Can't someone just patch the check out of the jar?
Anyone determined can change code that runs on their own PC, and no license system prevents that. What SunLicense stops is the easy route: sharing a key or a bought jar. Each key works on the number of PCs you choose, refunded and leaked keys stop on the next check, and on Standard every copy downloaded through SunLicense carries a hidden mark that tells you whose copy leaked.
How much does it cost?
The Free plan covers three products, 100 licenses and 10,000 license checks a month, with no credit card. Lite is $5 a month for 5 products and 2,500 licenses. License checks from players' games are never refused because of your plan, even if you go over.