500 次免费 KYC 会话。
每月。永久。

# Didit Free KYC — integrate in 5 minutes

You are integrating Didit's full KYC bundle (ID + Passive Liveness +
Face Match + Device & IP Analysis) into <my_stack>. The first 500 sessions every
month are free, forever, on every account — no credit card, no sales
call. Past 500 you keep using the same endpoint at $0.33 per session.
Every URL, header, and enum value below is canonical — do not paraphrase.

## 1. Provision an account
- Sign up: https://business.didit.me (no credit card required).
- Or provision programmatically: POST https://apx.didit.me/auth/v2/programmatic/register/
  (returns an API key bound to the workspace + application).
- The 500-session monthly free quota is counted at the workspace level.
  It resets at 00:00 UTC on the first of each month and applies to any
  workflow that combines the four bundled features.

## 2. Create the KYC workflow (one time)
POST https://verification.didit.me/v3/workflows/
Authorization header:  x-api-key: <your-api-key>
Body: workflow_label, features array with the four bundled entries
      [
        { feature: "ID_VERIFICATION" },
        { feature: "LIVENESS" },
        { feature: "FACE_MATCH" },
        { feature: "IP_ANALYSIS" }
      ]   (UPPERCASE — strict enum, do not lowercase)

This is the same workflow used in production at $0.33 per session.
Sessions counted under the 500-session free quota run on the same model
weights, the same edge nodes, the same Spain-Tesoro-attested pipeline.
There is no degraded model on the free tier.

## 3. Create a verification session for an end user
POST https://verification.didit.me/v3/session/
Body: workflow_id (from step 2), vendor_data (your own user id).
Response: session_url — redirect the user to it.

The hosted UI walks the user through document capture, selfie capture
(passive liveness), automatic face-match between portrait and selfie,
and Device & IP analysis on the originating connection. End-to-end inference is
sub-2 seconds across the full bundle.

## 4. Webhooks
- Register a webhook destination once via
  POST https://verification.didit.me/v3/webhook/destinations/
  Body: url, subscribed_events: ["session.verified", "session.review_started",
                                  "session.declined", "kyc_expired"]
- Response includes secret_shared_key — store it.
- Every webhook delivery carries an X-Signature-V2 header you MUST verify
  before trusting the payload.  HMAC-SHA256 verification MUST run against the raw body bytes (the raw payload as Didit sent it) BEFORE any JSON parsing — re-serialising the parsed body changes whitespace and key order, which invalidates the signature.Algorithm:
    1. sortKeys(payload) recursively
    2. shortenFloats (truncate trailing zeros after the decimal point)
    3. JSON.stringify the result
    4. HMAC-SHA256 with the secret_shared_key
    5. Hex-encode, compare to the X-Signature-V2 header.

## 5. Reading the session report
The session payload includes one object per bundled feature:
- id_verification — status, document_type, document_number, full_name,
  date_of_birth, expiration_date, issuing_state, parsed address, image
  quality scores, warnings.
- liveness — status, method ("PASSIVE"), score 0-100, reference_image,
  warnings.
- face_match — status, similarity score 0-100, source ("DOCUMENT"),
  target ("SELFIE").
- ip_analysis — status, ip, country, city, vpn, proxy, tor, hosting,
  asn, abuse_score, risk warnings.

Statuses use exact casing: "Approved", "Declined", "In Review",
"Expired", "Not Finished".

## 6. Hard rules — do not change
- Base URL for /v3/* endpoints is verification.didit.me (NOT apx.didit.me).
- Feature enums are UPPERCASE: ID_VERIFICATION, LIVENESS, FACE_MATCH, IP_ANALYSIS.
- Auth header is x-api-key (lowercase, hyphenated).
- Webhook signature header is X-Signature-V2 (NOT X-Signature).
- Always verify webhook signatures before trusting payload data.
- Status casing matches exactly: "Approved", "Declined", "In Review",
  "Expired", "Not Finished" (title-cased, space-separated).

## 7. Pricing reference (public)
- First 500 sessions per workspace per month: free, forever, no credit
  card, on every account. Quota resets 00:00 UTC on the first of each month.
- Overflow past 500 in a month: $0.33 per session, billed only for the
  sessions above the free quota. Same workflow, same endpoint, same
  features, same response shape.
- No minimums, no contracts, no overage surprises. The full price table:
  didit.me/pricing.

## 8. Verify your integration
- Sandbox starts on signup at https://business.didit.me — no separate flag.
- Test data: deterministic synthetic documents and selfies returned in
  sandbox. Sandbox sessions do not count against the 500 monthly free quota.
- Switch to live: flip the application's environment toggle in console.

When in doubt: https://docs.didit.me/sessions-api/create-session