Stamp image
US–1851–01c–0003
1¢
Verified · alpharomeodeltallc
Founded 2026 · Stewarded by the community · CC0A free, open record of every
A free, open record of every
stamp ever issued.
Look up any stamp and see who vouched for every detail — no account needed. Create a free account to add what you know. The catalog belongs to the collectors.
Don't know the OSID? Start from a photograph with Assisted Identification.
Recently verified · 301 records
Browse the catalog →Every stamp gets a page like this.
For collectors
Start with the stamp in your hand.
01
Find a stamp
Search by description, country, or year — or paste an OSID if you have one. No account required.
Browse the catalog →02
Identify from a photograph
Not sure what you're holding? Assisted Identification reads a photo and proposes catalog candidates — you decide which is right.
Try identification →03
Contribute what's missing
Holding a stamp the catalog doesn't have yet? Add it. The OSID is assigned automatically and the community reviews.
Contribute a record →Building something? The catalog is CC0-licensed and reachable through the OSID resolver and the API, with access tiers for developers and institutions.
Developer docs →Stewardship
Maintained by collectors, in the open.
- Open
- Every record is public domain under CC0. What the community builds here can never be locked away or sold back to you.
- Verified
- Every fact names who contributed it and who reviewed it. Disagreement happens on the page, not behind it.
- Plain
- No streaks, no feeds, no nagging — a well-kept library, not a storefront.
OSC is operated by Alpha Romeo Delta LLC, which holds final editorial authority over the catalog, exercised transparently and in public. Stewards, appointed from proven contributors, share day-to-day editorial work. The founding documents — the OSID specification, the contribution spec, and the governance charter — are versioned, public, and amendable through proposal.
The catalog is dedicated to the public domain under CC0, and the OSID format library is openly licensed for anyone to build on. Every record is public domain and every edit is public history — the records can never belong to any company, including ours.