Drop-in passwordless re-auth for returning users. No SMS bill, no SIM-swap exposure, no carrier round-trip. Same iBeta Level 1 PAD (presentation attack detection) engine as sign-up. $0.10 per auth, 500 free/month.
Robinhood Ventures
Trusted by 2,000+ organizations worldwide.
Phishing-proof login
Reuse the verified identity from sign-up to authenticate returning users. SIM-swap-proof, phishing-proof, $0.10 per call, cheaper than a typical SMS round-trip on every market.
Pick the checks you want, ID, liveness, face match, sanctions, address, age, phone, email, custom questions. Drag them into a flow in the dashboard, or post the same flow to our API. Branch on conditions, run A/B tests, no code required.
Embed natively with our Web, iOS, Android, React Native, or Flutter SDK. Redirect to a hosted page. Or just send your user a link, by email, SMS, WhatsApp, anywhere. Pick what fits your stack.
Didit hosts the camera, the lighting cues, the mobile hand-off, and accessibility. While the user is in the flow, we score 200+ fraud signals in real time and verify every field against authoritative data sources. Result in under two seconds.
Real-time signed webhooks keep your database in sync the moment a user is approved, declined, or sent to review. Poll the API on demand. Or open the console to inspect every session, every signal, and manage cases your way.
$ curl -X POST https://verification.didit.me/v3/session/ \
-H "x-api-key: $DIDIT_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"workflow_id": "wf_bio_auth",
"vendor_data": "user-42",
// base64-encoded reference selfie, ≤ 1MB
// omit this field for liveness-only mode
"portrait_image": "/9j/4AAQSkZJRgABAQE..."
}'portrait_image for face match; omit it for liveness-only.docs →// Your endpoint receives a signed payload
app.post("/webhooks/didit", (req, res) => {
const sig = req.headers["x-signature-v2"];
const expected = crypto.createHmac("sha256", SECRET)
.update(req.rawBody).digest("hex");
if (sig !== expected) return res.sendStatus(401);
const { status, decision, vendor_data } = req.body;
// status: Approved | Declined | In Review | ...
res.sendStatus(200);
});# Didit Biometric Authentication — integrate in 5 minutes
You are integrating Didit's Biometric Authentication module into <my_stack>.
This is a returning-user passwordless re-verification flow — a drop-in
replacement for SMS or email 2FA at high-value actions (large transfers,
password reset, large withdrawals, sensitive setting changes). It is NOT
the first-time KYC sign-up flow — for that, see Didit Liveness at
docs.didit.me/core-technology/liveness/overview.
Every URL, header, and enum value below is canonical — do not paraphrase
or "improve" them.
## 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).
## 2. Create the biometric_authentication workflow (one time)
Biometric Authentication is a workflow_type, not a feature flag. Create
the workflow once, reuse the workflow_id for every authentication.
POST https://verification.didit.me/v3/workflows/
Header: x-api-key: <your-api-key>
Body:
- workflow_label (your label, e.g. "step-up-2fa")
- workflow_type "biometric_authentication" (snake_case enum)
- features the array
[{ feature: "LIVENESS" }] (liveness-only mode)
OR
[{ feature: "LIVENESS" }, { feature: "FACE_MATCH" }] (face-match mode)
- liveness_method "PASSIVE" | "FLASHING" | "ACTIVE_3D" (PASSIVE recommended for low-friction step-up)
Store the returned workflow_id — you will reuse it on every auth.
## 3. Authenticate a returning user
POST https://verification.didit.me/v3/session/
Header: x-api-key: <your-api-key>
Header: Content-Type: application/json
Body:
- workflow_id (from step 2)
- vendor_data (your own user id, e.g. "user-42")
- callback (optional URL we redirect the user to after capture)
- metadata (optional JSON, surfaced back on the webhook)
- portrait_image (Base64 JPEG, REQUIRED when the workflow has FACE_MATCH;
OMIT for liveness-only mode)
The portrait_image is the stored reference photo from the user's original
KYC verification (you already have it as id_verification.portrait_image in
the original session response). Send it as a Base64-encoded JPEG, max 1 MB.
Response: session_url — redirect the user to it. Didit hosts the capture
(camera, motion prompts, low-light fallback, accessibility) and posts the
verdict back via webhook.
## 4. Webhooks
- Register a webhook destination once via
POST https://verification.didit.me/v3/webhook/destinations/
Body: url, subscribed_events: ["session.verified", "session.declined",
"session.review_started"]
- 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 report
The webhook payload (and the GET /v3/session/{id}/decision/ response)
returns the combined biometric_authentication shape:
status "Approved" | "Declined" | "Not Finished"
workflow_id string
session_id uuid
session_number integer
vendor_data your user id
liveness:
status "Approved" | "Declined" | "Not Finished"
method "PASSIVE" | "FLASHING" | "ACTIVE_3D"
score number 0-100
reference_image signed URL to the captured selfie (expires in 1 hour)
video_url signed URL (FLASHING and ACTIVE_3D only, expires in 1 hour)
warnings array
face_match: (only present in face-match mode)
status "Approved" | "Declined" | "Not Finished"
score number 0-100 (similarity %)
source_image signed URL to the captured selfie
target_image signed URL to the supplied portrait_image
warnings array
Overall status is "Approved" only when liveness.status == "Approved" AND
(face_match is absent OR face_match.status == "Approved").
Auto-decline triggers (always enforced by Didit, not configurable):
FACE_IN_BLOCKLIST, NO_FACE_DETECTED, LIVENESS_FACE_ATTACK, NO_REFERENCE_IMAGE
Configurable risks (action per workflow — Decline, Review, or Approve):
LOW_LIVENESS_SCORE, LOW_FACE_MATCH_SIMILARITY
## 6. Hard rules — do not change
- Base URL for /v3/* endpoints is verification.didit.me (NOT apx.didit.me).
- workflow_type is snake_case: biometric_authentication.
- Feature enums inside the workflow are UPPERCASE: LIVENESS, FACE_MATCH.
- Liveness method enum is UPPERCASE: PASSIVE, FLASHING, ACTIVE_3D.
- 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",
"Not Finished" (title-cased, space-separated).
- portrait_image is Base64 JPEG, max 1 MB, required only in face-match mode.
## 7. Pricing reference (public)
- Biometric Authentication: $0.10 per authentication (passwordless re-auth).
- 500 free authentications every month, forever, on every account.
- For the original sign-up KYC, see https://didit.me/pricing (full KYC
bundle is $0.33 per onboarded user, which includes Liveness + Face Match +
ID Verification + Device & IP Analysis).
## 8. When to use this versus Liveness directly
- First-time KYC sign-up: use Liveness (the feature) inside an ID
Verification workflow. See docs.didit.me/core-technology/liveness/overview.
- Step-up at sensitive actions (transfer, password reset, large
withdrawal): use this Biometric Authentication workflow.
- High-volume passive monitoring (any login): use this workflow with
liveness-only mode (no portrait_image) — fastest, lowest friction.
## 9. Verify your integration
- Sandbox starts on signup at https://business.didit.me — no separate flag.
- Test images: deterministic synthetic faces returned in sandbox
(Approved by default; trigger Declined by sending the canonical "spoof"
test image).
- Switch to live: flip the application's environment toggle in console.
When in doubt: https://docs.didit.me/core-technology/biometric-auth/overview
$0 / month. No credit card required.
Pay only for what you use. 25+ modules. Public per-module pricing, no monthly minimum fee.
Custom MSA & SLA. For large volumes and regulated programs.
Start free → pay only when a check runs → unlock Enterprise for a custom contract, SLA, or data residency.
Didit is infrastructure for identity and fraud, the platform we wished existed when we were building products ourselves: open, flexible, and developer-friendly, so it works as a real part of your stack instead of a black box you integrate around.
One API covers verifying people (KYC, know your customer), verifying businesses (KYB, know your business), screening crypto wallets (KYT, know your transaction), and monitoring transactions in real time, on a stack built to be:
The footprint underneath: 14,000+ document types in 48+ languages, 1,000+ data sources, and 200+ fraud signals on every session. The Didit infrastructure dynamically learns from every session and gets better every day.
workflow_type (snake-case: biometric_authentication) that composes the LIVENESS feature with an optional FACE_MATCH feature. Liveness on its own is the sign-up capability, see /products/liveness for the first-time know-your-customer (KYC) flow. Both use the same iBeta Level 1 Presentation Attack Detection (PAD)-certified engine, so the model your user passed at onboarding is the same model checking them at every login.status (Approved, Declined, Not Finished), a liveness block with status, method (PASSIVE, FLASHING, or ACTIVE_3D), score 0-100, reference_image, video_url, and warnings, plus a face_match block (only present when the workflow has FACE_MATCH) with status, score 0-100, source_image, target_image, and warnings. The signed image and video URLs expire after 60 minutes. Overall status is Approved only when liveness is approved AND (face match is absent OR face match is approved).The full flow normally takes under 30 seconds end-to-end, pick up the ID, snap the document, snap the selfie, done. That is the fastest in the market. Legacy KYC providers usually take more than 90 seconds for the same flow.
On the back end, Didit returns the result in under two seconds at p99, measured from the moment the user finishes the selfie to the moment your webhook fires. Mobile capture is tuned for slow phones and slow networks: progressive image compression, lazy software development kit load, and a one-tap hand-off from desktop to phone via QR code if the user starts on web.
FACE_IN_BLOCKLIST, NO_FACE_DETECTED, LIVENESS_FACE_ATTACK, and NO_REFERENCE_IMAGE. Configurable warnings, LOW_LIVENESS_SCORE and LOW_FACE_MATCH_SIMILARITY, let you tune the review and decline thresholds per application.Every session lands on one of seven clear statuses, so your code always knows what to do:
Approved, every check passed. Move the user forward.Declined, one or more checks failed. You can allow the user to resubmit the specific failed step (for example, re-take the selfie) without re-running the whole flow.In Review, flagged for compliance review. Open the case in the console, see every signal, decide approve or decline.In Progress, user is mid-flow.Not Started, link sent, user has not opened it yet. Send a reminder if it sits too long.Abandoned, user opened the link but did not finish in time. Re-engage or expire.Expired, the session link aged out. Create a new session.A signed webhook fires on every status change, so your database always stays in sync. Abandoned and declined sessions are free.
Production data is processed and stored in the European Union by default, on Amazon Web Services. Enterprise contracts can request alternative regions for jurisdictions whose regulators require it.
Encryption everywhere. AES-256 at rest across every database, object store, and backup. Transport Layer Security 1.3 in transit on every API call, webhook, and Business Console session. Biometric data is encrypted under a separate Customer Master Key.
Retention is yours to control. Default retention is indefinite (unlimited) unless you configure shorter, between 30 days and 10 years per application, and you can delete any individual session at any time from the dashboard or the API.
Certifications: SOC 2 Type 1 (Type 2 audit in progress), ISO/IEC 27001:2022, iBeta Level 1 PAD, and a public attestation from Spain''s Tesoro / SEPBLAC / CNMV that Didit''s remote identity verification is safer than verifying someone in person. Full report at /security-compliance.
Didit ships compliant by default for the regulators that matter to identity infrastructure:
Detailed memo, every certificate, every regulator letter: /security-compliance.
Three integration paths, pick whichever fits your stack:
Same dashboard, same billing, same pay-per-success price for all three. Step-by-step guide at docs.didit.me/integration/integration-prompt.
One API for KYC, KYB, Transaction Monitoring, and Wallet Screening. Integrate in 5 minutes.