Methodology

What this registry is

The Slot RTP Registry is a public snapshot of what slot providers and casinos publish on their own websites. For each slot in the registry, we record the RTP value, configurable variants where exposed, volatility, max win, hit frequency, release year, and the source URL.

We do not claim to know the "real" RTP behind closed doors. Regulators (UKGC, NJ DGE, MGA) do not publish per-slot RTP — only aggregate operator statistics. Anyone claiming "true regulator-verified RTP per slot" is fabricating it.

Sources we collect from

Currently 15 slot providers. Each parser is custom because every site uses a different structure (HTML span, JSON blob, WordPress REST API, Wix CMS leakage, etc.).

Coverage status meanings

complete

More than 90% of the provider's catalog has usable RTP. Trust as primary source.

partial

50–90% coverage. Show with caveat. A second-pass scrape may help.

exhausted_public

The provider does not publish full RTP coverage on their public website. We record what we can.

Per-field confidence

Each field on each record carries a confidence label.

• high — extracted via strong DOM selector or canonical JSON blob.
• medium — regex fallback or structured text near a labeled field.
• low — best-effort extraction, may need verification.
• unavailable — the field is genuinely not present at the source.

Provenance & evidence

Every record carries:

• source_url — the page we read
• snapshot_id — sha256 of the full HTML body at fetch time
• fetched_at — ISO timestamp of the read
• parser_version — version of the extractor used

Snapshots (~270 MB across 4,076 source observations) are kept as gzipped HTML. If a provider changes their site, we can prove what we saw on a given date.

What v1 does not have yet

• Per-casino RTP variants. Phase 2 work — UK casino help pages publish them but most are behind anti-bot or geo-blocks.
• Historical changelog. Real history requires accumulated weekly snapshots; we start collecting from launch.
• Community session data. Empirical "actual" returns from real player sessions — needs anti-fraud + sample threshold first.
• All slot catalogs in existence. Some providers (BTG image-based RTP, ELK, Quickspin partial) are not yet usable at scale.

Versioning

The current data contract is v1.0.0. v1.x means additive only: more providers, more optional fields. No field removal. Breaking changes require a v2 with migration window.