isHuman Proof Network

Verify Humans Once.
Prove Locally Everywhere.

Like Stripe for payments — sites embed the Lemma SDK and users verify in-flow with a trusted IDV issuer. One verification, reusable across every Lemma-enabled site, validated locally in the browser with no phone-home.

Each site gets a derived, site-private PPID credential. Ed25519 signatures verify offline, revocation propagates quickly, and sites can enforce immediate local block decisions. Stripe Identity today; additional IDV issuers on roadmap.

Checking credentials...

IDV-issuer verified (Stripe today)
Ed25519 local verification
Site-private PPIDs

How Lemma.id Works

Verify a person once, derive site-private credentials, and run local checks for each session.

1

Verify Once

In-context on any site, the user completes IDV (Stripe Identity today; more issuers on roadmap) and receives a signed master isHuman credential.

2

Derive Per Site

Wallet bridge derives a site-bound credential using normalized hostname and wallet secret.

3

Verify Locally

Sites check signature, expiry, and revocation status in-browser with clear allow/deny reasons.

Master + Derived Credentials

Issue one master proof at lemma.id, then derive per-site credentials that preserve user privacy across domains.

PPID-Bound Privacy

Pairwise identifiers are derived per site, preventing simple cross-site correlation of user identity.

Local Verification Path

The SDK validates Ed25519 signatures, claims, and expiry without requiring a server call on each check.

Site-Scoped Blocking

Operators can block abuse immediately at the site level with deterministic check responses.

Network Revocation Review

Escalate severe abuse to network-wide revocation through an evidence-backed admin approval flow.

Simple Integration

Add a script tag and call verify() to get a fast human verdict plus PPID for your local policies.

Verification flow

Verification Happens In-Context, Not On Lemma

Users never have to travel to lemma.id. The SDK triggers verification in-flow on whichever site the user is on, the IDV provider runs there, and the signed credential lives in the user's browser wallet — not on a Lemma server.

First-time user, on any site

1

User on any site

Site loads the lemma.id SDK and calls verify().

2

Browser wallet check

SDK checks the user's browser wallet for an existing isHuman credential.

3

IDV issuer flow

None found. SDK launches in-context verification with an IDV issuer (Stripe Identity today).

4

Wallet stores credential

Signed master credential is written to the user's browser wallet — not to Lemma servers.

5

Site decision

Site receives a local Ed25519 verdict and a site-private PPID.

Returning user — any Lemma-enabled site

1

User on any site

SDK calls verify().

2

Browser wallet

Existing master credential is found locally.

3

Derive site PPID

Wallet derives a site-private credential from the master + this hostname.

4

Local verify

Ed25519 signature + revocation freshness checked entirely in-browser. No round-trip to Lemma.

5

Site decision

Site receives verdict and PPID for local policy.

The wallet works like a physical driver's license. The DMV doesn't get a notification when you show your license at a bar. Lemma doesn't either. Issuers sign once; sites verify locally; users carry the credential.

Where isHuman fits

Use cases that don't pencil out for full IDV

Per-user IDV at $1–2 doesn't make sense for low-margin or high-volume flows. isHuman pools verification cost across many sites, so any site can have human-grade signal at a few cents per check.

Waitlists & free trials

Block bot-funded list inflation and trial abuse without forcing $2 IDV on every signup.

Ticketing & releases

Stop scalper bots from buying inventory faster than humans. One reusable proof, not a CAPTCHA arms race.

Comments & forums

Reduce spam, sock-puppet networks, and brigading without storing PII on every relying site.

Dating & social

Suppress fake profiles and catfishing networks while keeping user identity site-private.

AI agent gating

Distinguish human users from autonomous agents without requiring agents to identify themselves.

Account integrity

Re-challenge suspicious accounts on demand using the doubt-and-refresh flow, with cost shifted onto the suspect transaction.

Proof of Humanity

One verification. Every site. Always local.

isHuman gives users a reusable human proof while preserving site privacy. Verify once through any trusted IDV issuer, in-flow on any site, then let sites verify locally with Ed25519-signed credentials and revocation freshness checks.

Verify Once

Users complete one IDV verification in-flow on whichever site they're on — no detour to lemma.id. The signed master credential is stored in the user's browser wallet.

Derive Per Site

The wallet bridge derives a site-bound credential on first request, so each integration gets its own PPID and privacy boundary.

Two-Tier Revocation

Sites can block instantly at the domain level, then escalate to evidence-based network revocation for coordinated abuse response.

Integrate in two lines
<script src="https://lemma.id/sdk/ishuman-verifier.js"></script>
<script>new IsHumanVerifier({ siteId: 'your-site-id' }).verify();</script>
Get Verified Add to Your Site

IDV-issuer verified • Ed25519-signed • Site-private PPIDs

Ship Proof-of-Humanity Without Building It Yourself

Launch reusable human verification, site-private derivation, and abuse controls with a production-ready SDK and API.

Get Verified View isHuman Docs

Verify once • Derive per site • Verify locally