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REST API — Build Custom Integrations

Full programmatic access to FastLinkIt. Create links, manage contacts, send mailings, accept payments, and more — all from your own code or CMS plugins.

Links & QR Codes API

Create, read, update, and delete short links and QR codes programmatically. Set custom short codes, UTM parameters, QR colours and logo, expiration dates, and track click statistics per link — all via simple JSON endpoints.

  • Full CRUD operations for links and QR codes
  • Custom short codes with availability validation
  • UTM parameters (source, medium, campaign, term, content)
  • QR code customisation (colours, logo)
  • Click analytics and statistics endpoints
  • Tag management per link
POST /api/links
{
  "destinationUrl": "https://example.com",
  "shortCode": "spring26",
  "title": "Spring Campaign",
  "qrCode": { "enabled": true }
}

Contacts & Groups API

Manage your contact database programmatically. Create contacts with full profiles including phones, addresses, websites, and notes. Organise them into groups, bulk-add members by email, and auto-create missing contacts on the fly.

  • Full contact CRUD with nested data
  • Phones, addresses, websites, and notes per contact
  • Contact groups with member management
  • Bulk member import by email
  • Search and pagination
  • Bounce and unsubscribe tracking
GET /api/contacts
Jane Doe
jane@example.com
Alex Smith
alex@example.com
Newsletter
42 members

Email Mailing API

Compose and send email campaigns programmatically. Select recipients from contacts or groups, use personalisation placeholders, queue mailings for delivery, and track per-recipient delivery status in real time.

  • Create draft mailings with HTML body
  • Add recipients from groups and individual contacts
  • Placeholder support (Name, Email, FirstName, LastName, Company)
  • Queue for background sending
  • Per-recipient delivery tracking
  • Automatic bounce and unsubscribe filtering
Mailing Status
Total Recipients 248
Sent 241
Failed 2
Skipped (bounced) 5

Organizer API

Manage planners (booking pages), event templates, availability slots, and bookings through the API. Build custom scheduling workflows, sync with external calendars, or embed booking functionality in your own applications.

  • Planner CRUD (booking pages with short codes)
  • Event template management
  • Batch availability slot creation
  • Booking management with status updates
  • Confirmed, cancelled, and pending states
  • Soft delete with restore capability
GET /api/organizer/bookings
Confirmed Jane Doe — 10:00 AM
Mar 20
Confirmed Alex Smith — 2:30 PM
Mar 20
Pending Chris Lee — 4:00 PM
Mar 21

Payment API

Accept payments via Stripe Connect destination charges. Create products, generate checkout sessions, track transactions, and process refunds — all programmatically. Webhook notifications with HMAC signing keep your systems in sync.

  • Product management with pricing
  • Quick checkout (no pre-created product required)
  • Stripe destination charges to your connected account
  • Full and partial refunds
  • Webhook delivery with HMAC signature verification
  • Source tracking per platform
Payment Flow
Your App FastLinkIt API
Checkout Stripe
Webhook Your App

GeoIP Lookup API

Look up geographic location data for any IP address. Get full details including continent, country, city, coordinates, ISP, connection type, and timezone. Results are cached in the database for fast repeat lookups.

  • Full and simple lookup endpoints
  • Look up caller's own IP with /me
  • Continent, country, and city resolution
  • Coordinates and timezone
  • ISP and connection type detection
  • EU country identification
GET /api/geoip/8.8.8.8
{
  "country": "United States",
  "city": "Mountain View",
  "isp": "Google LLC",
  "timezone": "America/Los_Angeles",
  "isEuCountry": false
}

Scoped API Keys

Generate API keys with granular permissions. Select exactly which services each key can access — links, contacts, mailings, payments, and more. Follow the principle of least privilege without compromising on functionality.

  • 10 configurable scopes (links, QR, contacts, groups, mailings, etc.)
  • Full access or restricted per key
  • Per-key expiration dates
  • Usage tracking (last used timestamp)
  • Revoke anytime with immediate effect
  • Plan-based access enforcement
API Key Scopes
Links QR Codes Contacts Groups Mailings Organizer Payments GeoIP Files Tags
fli_a1b2c3d4... — Last used 2 hours ago

Authentication

Three authentication methods to suit every integration scenario. Use JWT Bearer tokens for server-to-server communication, API keys via the X-Api-Key header for simple integrations, or cookie auth for the web UI.

  • JWT Bearer tokens (login with credentials)
  • API Key authentication via X-Api-Key header
  • Interactive OpenAPI documentation (Scalar UI)
  • Plan-based usage limits enforced on all endpoints
  • CORS support for browser-based integrations
Authentication Methods
JWT Authorization: Bearer eyJhbGci...
API Key X-Api-Key: fli_a1b2c3d4...
Cookie Browser session (web UI)

Frequently Asked Questions

Everything you need to know about the FastLinkIt REST API.

What authentication methods does the API support?

FastLinkIt supports three authentication methods: JWT Bearer tokens for server-to-server integrations, API keys via the X-Api-Key header for simple programmatic access, and cookie authentication for the web UI. JWT tokens are obtained by posting credentials to the /api/auth/login endpoint. API keys are generated from your account settings.

How do I create an API key?

Go to Account > API Keys in the FastLinkIt dashboard. Click "Generate New Key", give it a name and optional expiration date, then select which scopes (permissions) the key should have. The raw key is shown only once — copy it immediately. Keys use the fli_ prefix for easy identification.

What are API key scopes?

Scopes let you limit what each API key can do. There are 10 configurable scopes covering links, QR codes, contacts, groups, mailings, organizer, payments, GeoIP, files, and tags. You can grant full access or restrict a key to only the services it needs, following the principle of least privilege.

Is there a rate limit?

API usage is governed by your subscription plan. Each plan defines monthly limits for link and QR code creation, file upload sizes, and storage quotas. The API enforces these same limits, so a Starter plan allows 10 links per month whether created via the dashboard or the API.

Which plans include API access?

API access is available on all plans. Free plan users can create up to 5 links per month via the API. Higher plans unlock more link capacity, larger file uploads, additional storage, and advanced features like contacts, mailings, and the organizer.

Where can I find the full API documentation?

Full interactive API documentation is available via the Scalar UI at /scalar/v1 on your FastLinkIt instance. The OpenAPI specification is published at /openapi/v1.json, which you can import into Postman, Insomnia, or any OpenAPI-compatible tool.

Can I accept payments through the API?

Yes. The Payment API lets you create products, generate Stripe Checkout sessions with destination charges, track transactions, and process full or partial refunds. Payments flow through Stripe Connect, so funds go directly to your connected Stripe account with a configurable platform fee. Webhook notifications with HMAC signing keep your systems in sync.

Start Building with the API Today

Create your free account in seconds. No credit card required.
Generate an API key, explore the interactive docs, and ship your first integration.

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