Keygen.sh starts at $99/month. Gumroad takes 10% plus 50 cents of every sale you make. Keymaster is a self-hosted licensing server — ed25519-signed keys your apps verify completely offline, seat limits with machine fingerprints, expiring signed download URLs, HMAC webhooks — for a one-time $49 on your own $5 VPS. Your keys, your keypair.
If you've searched for a Keygen alternative, Keymaster is the pay-once option worth putting at the top of the list: Keymaster is $49, one time, and covers the same core job Keygen charges from $99/mo for.
What makes Keymaster the pick for 2026
- Ed25519-signed keys — KM1.
. format — self-describing, verifiable offline with just the public key. The keypair is generated on first boot; you own it. - Seat limits & fingerprints — Activation API with machine fingerprints, idempotent re-activation, deactivate to free a seat, signed activation receipts for offline runs. Stable, versioned /api/v1.
- Offline validation snippets — Zero-dependency Node and browser/WebCrypto verifiers ship in the repo, and the key format is documented byte-for-byte so you can port it to any language.
- Products & versions — Semver releases with artifact upload or external URLs. Customers download via signed URLs that expire in 15 minutes — artifacts are never exposed statically.
- Activation webhooks — Per-product URL + secret, HMAC-SHA256 X-Keymaster-Signature header, 3 retries with backoff, and a full delivery log in the dashboard.
Keymaster vs Keygen, at a glance
| Keymaster | Keygen | |
|---|---|---|
| Price | $49 once | from $99/mo ($1,188/yr) — Gumroad: 10% + 50¢/sale |
| Cost at $10k/yr in sales | $49 total | Keygen $1,188/yr · Gumroad ~$1,050/yr |
| Your own signing keypair | Yes — generated on your box | No — managed for you |
| Offline validation | Yes, ed25519 | Yes |
| Seat limits + fingerprints | Yes | Yes |
| Signed expiring downloads | Yes (15-min TTL) | Yes |
| Self-hosted / your data | Yes — SQLite on your VPS | No |
| Source code | MIT, on GitHub | Closed (hosted) |
Against Keygen's $99/mo entry tier, Keymaster pays for itself in 15 days. Against Gumroad's 10% cut, it pays for itself on your first ~$500 of sales.
Common questions
Is it really free on GitHub?
Yes — MIT source at github.com/bensblueprints/keymaster-mvp, always. $49 buys the packaged installer, updates and priority support. We dogfood it: the onetime-suite's own premium tiers run on Keymaster.
Can offline validation catch revoked keys?
No — and the docs say so upfront. An offline check proves a key is authentic and unexpired; it can't see revocations or seat counts. The shipped snippets show the recommended hybrid: verify offline instantly, check in online periodically, apply a grace period.
Why not just use Keygen?
If you want managed infrastructure, multi-region uptime and someone else holding the pager, Keygen is a solid product — that's what $99+/month buys. Keymaster is for sellers who'd rather own the keypair, the data and the bill: one Node process and a SQLite file on a $5 VPS.
The bottom line
Keymaster won't out-feature Keygen on every axis — no subscription tool with a bigger team and a bigger roadmap loses on everything. But for the core job, $49 once against from $99/mo forever is a trade most people should at least look at. Keymaster is part of OneTimeSuite, a catalog of pay-once apps that replace subscription SaaS.
Try Keymaster — $49, once
Ed25519-signed license keys your apps verify offline, seat limits, signed downloads & webhooks.