REST API

303Happenings Event API

Q: How do I authenticate API requests?

Include your API key in the X-API-Key header with every request. Keys are generated in your developer dashboard after signing up.

Q: What data formats do you support?

All responses are JSON. Dates are ISO 8601 with timezone. Coordinates use WGS84 (latitude/longitude). Images return CDN URLs.

Q: Can I use the API for a commercial product?

Yes. All paid tiers allow commercial use. Attribution to 303Happenings is appreciated but not required for Growth and Enterprise tiers.

Q: What happens if I exceed my rate limit?

Requests beyond your limit return HTTP 429 with a Retry-After header. The X-RateLimit-Remaining header shows your current allowance. Upgrade your tier for higher limits.

Q: Do you offer a free trial?

New accounts get a 7-day free trial on the Starter tier. No credit card required. After the trial, choose a paid plan to continue.

Access Denver's most comprehensive event data. Build apps, power concierge services, enrich travel platforms. Real-time data from 24 scrapers, 156 database tables, and thousands of verified venues.

<100ms avg response99.9% uptime SLAReal-time event dataTrusted by Denver apps

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Starter

For hobby projects and prototypes

$49/mo

1,000 requests/day

60/min rate limit

Events + Venues endpoints
JSON responses
Community support
API key dashboard

Getting Started

Three steps to your first API call. No SDK required.

Create an Account

Get Your API Key

Generate a key from your developer dashboard. Choose a tier that fits your usage.

Make Your First Request

Include your key in the X-API-Key header. All endpoints return JSON.

Authentication

All API requests require the X-API-Key header. Here is a simple request to list upcoming events:

curl -H "X-API-Key: your_key_here" \
  "https://api.303happenings.com/api/v1/events?limit=5"

API Reference

All endpoints are served from https://api.303happenings.com/api/v1

GET

/api/v1/events

Search and list upcoming events in Denver. Supports filtering by category, date range, neighborhood, venue, and keyword search. Results are sorted by discovery score and start time.

Parameters

Name	Type	Required	Description
`q`	string	No	Full-text search query (title, venue, description)
`category`	string	No	Event category: concert, sports, comedy, theater, festival, food, art, community, nightlife, family, outdoor
`neighborhood`	string	No	Filter by Denver neighborhood slug (e.g., rino, lodo, capitol-hill)
`venue_id`	uuid	No	Filter by venue ID
`start_date`	ISO 8601	No	Start of date range (default: now)
`end_date`	ISO 8601	No	End of date range (default: 30 days from now)
`free`	boolean	No	Only return free events
`limit`	integer	No	Results per page (default: 20, max: 100)
`offset`	integer	No	Pagination offset (default: 0)

Example Request

curl -H "X-API-Key: dk_live_abc123" \
  "https://api.303happenings.com/api/v1/events?category=concert&limit=2"

Example Response

{
  "data": [
    {
      "id": "550e8400-e29b-41d4-a716-446655440000",
      "title": "Nathaniel Rateliff & The Night Sweats",
      "slug": "nathaniel-rateliff-night-sweats-red-rocks-2026",
      "category": "concert",
      "startDatetime": "2026-06-15T19:30:00-06:00",
      "endDatetime": "2026-06-15T23:00:00-06:00",
      "description": "Colorado native Nathaniel Rateliff returns to Red Rocks...",
      "imageUrl": "https://cdn.303happenings.com/events/rateliff-rr.jpg",
      "isFree": false,
      "priceMin": 65.00,
      "priceMax": 195.00,
      "discoveryScore": 92,
      "venue": {
        "id": "7c9e6679-7425-40de-944b-e07fc1f90ae7",
        "name": "Red Rocks Amphitheatre",
        "slug": "red-rocks-amphitheatre",
        "neighborhood": "Morrison",
        "latitude": 39.6654,
        "longitude": -105.2057
      },
      "url": "https://www.303happenings.com/event/nathaniel-rateliff-night-sweats-red-rocks-2026"
    }
  ],
  "meta": {
    "total": 847,
    "limit": 2,
    "offset": 0,
    "hasMore": true
  }
}

GET

/api/v1/events/:id

Get full details for a single event, including pricing, performers, venue info, and structured data. Use the event UUID from list results.

Parameters

Name	Type	Required	Description
`id`	uuid	Yes	Event ID (UUID)

Example Request

curl -H "X-API-Key: dk_live_abc123" \
  "https://api.303happenings.com/api/v1/events/550e8400-e29b-41d4-a716-446655440000"

Example Response

{
  "data": {
    "id": "550e8400-e29b-41d4-a716-446655440000",
    "title": "Nathaniel Rateliff & The Night Sweats",
    "slug": "nathaniel-rateliff-night-sweats-red-rocks-2026",
    "category": "concert",
    "startDatetime": "2026-06-15T19:30:00-06:00",
    "endDatetime": "2026-06-15T23:00:00-06:00",
    "description": "Colorado native Nathaniel Rateliff returns to Red Rocks...",
    "imageUrl": "https://cdn.303happenings.com/events/rateliff-rr.jpg",
    "isFree": false,
    "priceMin": 65.00,
    "priceMax": 195.00,
    "discoveryScore": 92,
    "performers": ["Nathaniel Rateliff", "The Night Sweats"],
    "tags": ["outdoor", "rock", "colorado-artist"],
    "venue": {
      "id": "7c9e6679-7425-40de-944b-e07fc1f90ae7",
      "name": "Red Rocks Amphitheatre",
      "slug": "red-rocks-amphitheatre",
      "address": "18300 W Alameda Pkwy, Morrison, CO 80465",
      "neighborhood": "Morrison",
      "latitude": 39.6654,
      "longitude": -105.2057,
      "capacityTier": "large"
    },
    "sources": ["ticketmaster", "seatgeek"],
    "url": "https://www.303happenings.com/event/nathaniel-rateliff-night-sweats-red-rocks-2026"
  }
}

GET

/api/v1/venues

Search and list verified Denver venues. Filter by type, neighborhood, or search by name. Includes geo coordinates for map integrations.

Parameters

Name	Type	Required	Description
`q`	string	No	Search by venue name
`type`	string	No	Venue type: bar, restaurant, arena, park, theater, gallery, club, stadium, brewery, museum
`neighborhood`	string	No	Neighborhood slug
`capacity`	string	No	Capacity tier: intimate, small, medium, large
`limit`	integer	No	Results per page (default: 20, max: 100)
`offset`	integer	No	Pagination offset (default: 0)

Example Request

curl -H "X-API-Key: dk_live_abc123" \
  "https://api.303happenings.com/api/v1/venues?type=brewery&neighborhood=rino&limit=3"

Example Response

{
  "data": [
    {
      "id": "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
      "name": "Ratio Beerworks",
      "slug": "ratio-beerworks",
      "type": "brewery",
      "neighborhood": "rino",
      "address": "2920 Larimer St, Denver, CO 80205",
      "latitude": 39.7621,
      "longitude": -104.9804,
      "capacityTier": "medium",
      "isVerified": true,
      "upcomingEventCount": 3,
      "url": "https://www.303happenings.com/venue/ratio-beerworks"
    }
  ],
  "meta": {
    "total": 12,
    "limit": 3,
    "offset": 0,
    "hasMore": true
  }
}

GET

/api/v1/venues/:id

Get full details for a single venue including metadata, hours, parking info, and upcoming event count.

Parameters

Name	Type	Required	Description
`id`	uuid	Yes	Venue ID (UUID)

Example Request

curl -H "X-API-Key: dk_live_abc123" \
  "https://api.303happenings.com/api/v1/venues/a1b2c3d4-e5f6-7890-abcd-ef1234567890"

Example Response

{
  "data": {
    "id": "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
    "name": "Ratio Beerworks",
    "slug": "ratio-beerworks",
    "type": "brewery",
    "neighborhood": "rino",
    "address": "2920 Larimer St, Denver, CO 80205",
    "latitude": 39.7621,
    "longitude": -104.9804,
    "capacityTier": "medium",
    "isVerified": true,
    "metadata": {
      "website": "https://ratiobeerworks.com",
      "parking": "Street parking available",
      "transitNearby": ["38th & Blake Station"]
    },
    "upcomingEventCount": 3,
    "url": "https://www.303happenings.com/venue/ratio-beerworks"
  }
}

GET

/api/v1/venues/:id/events

List upcoming events at a specific venue. Useful for venue detail pages and digital signage.

Parameters

Name	Type	Required	Description
`id`	uuid	Yes	Venue ID (UUID)
`limit`	integer	No	Results per page (default: 20, max: 100)
`offset`	integer	No	Pagination offset (default: 0)

Example Request

curl -H "X-API-Key: dk_live_abc123" \
  "https://api.303happenings.com/api/v1/venues/a1b2c3d4-e5f6-7890-abcd-ef1234567890/events?limit=5"

Example Response

{
  "data": [
    {
      "id": "550e8400-e29b-41d4-a716-446655440000",
      "title": "Trivia Tuesday at Ratio",
      "category": "community",
      "startDatetime": "2026-03-17T19:00:00-06:00",
      "isFree": true,
      "discoveryScore": 68
    }
  ],
  "meta": {
    "total": 3,
    "limit": 5,
    "offset": 0,
    "hasMore": false
  }
}

GET

/api/v1/neighborhoods

List Denver neighborhoods with metadata, event counts, and character descriptions. Growth and Enterprise tiers only.

Example Request

curl -H "X-API-Key: dk_live_abc123" \
  "https://api.303happenings.com/api/v1/neighborhoods"

Example Response

{
  "data": [
    {
      "slug": "rino",
      "name": "RiNo (River North Art District)",
      "description": "Denver's creative hub with street art, breweries, and converted warehouses.",
      "latitude": 39.7621,
      "longitude": -104.9804,
      "eventCount": 45,
      "venueCount": 38,
      "topCategories": ["art", "nightlife", "food"]
    },
    {
      "slug": "lodo",
      "name": "LoDo (Lower Downtown)",
      "description": "Historic district near Union Station with sports venues, restaurants, and bars.",
      "latitude": 39.7530,
      "longitude": -104.9995,
      "eventCount": 62,
      "venueCount": 54,
      "topCategories": ["sports", "nightlife", "concert"]
    }
  ],
  "meta": {
    "total": 25
  }
}

GET

/api/v1/trending

Get trending events and venues based on discovery score momentum, ticket velocity, and social signals. Growth and Enterprise tiers only.

Parameters

Name	Type	Required	Description
`type`	string	No	Filter by 'events' or 'venues' (default: both)
`limit`	integer	No	Results per type (default: 10, max: 50)

Example Request

curl -H "X-API-Key: dk_live_abc123" \
  "https://api.303happenings.com/api/v1/trending?type=events&limit=5"

Example Response

{
  "data": {
    "events": [
      {
        "id": "550e8400-e29b-41d4-a716-446655440000",
        "title": "Nathaniel Rateliff at Red Rocks",
        "category": "concert",
        "startDatetime": "2026-06-15T19:30:00-06:00",
        "discoveryScore": 92,
        "trendScore": 8.5,
        "venue": {
          "name": "Red Rocks Amphitheatre",
          "slug": "red-rocks-amphitheatre"
        }
      }
    ],
    "venues": []
  },
  "meta": {
    "generatedAt": "2026-03-13T12:00:00Z",
    "window": "7d"
  }
}

Rate Limiting

Every response includes rate limit headers so you can track your usage and avoid hitting limits.

Header	Description	Example
`X-RateLimit-Limit`	Your daily request limit based on your tier	10000
`X-RateLimit-Remaining`	Requests remaining in the current day	9542
`X-RateLimit-Per-Minute`	Per-minute burst limit for your tier	300
`X-RateLimit-Reset`	UTC timestamp when the daily limit resets (midnight UTC)	2026-03-14T00:00:00Z
`Retry-After`	Seconds to wait before retrying (only on 429 responses)	42

Tip: If you receive a 429 Too Many Requests response, check the Retry-After header and wait that many seconds before your next request. Implement exponential backoff for production applications.

Frequently Asked Questions

How do I authenticate API requests?

Include your API key in the X-API-Key header with every request. Keys are generated in your developer dashboard after signing up.

What data formats do you support?

All responses are JSON. Dates are ISO 8601 with timezone. Coordinates use WGS84 (latitude/longitude). Images return CDN URLs.

Can I use the API for a commercial product?

Yes. All paid tiers allow commercial use. Attribution to 303Happenings is appreciated but not required for Growth and Enterprise tiers.

What happens if I exceed my rate limit?

Requests beyond your limit return HTTP 429 with a Retry-After header. The X-RateLimit-Remaining header shows your current allowance. Upgrade your tier for higher limits.

Do you offer a free trial?

New accounts get a 7-day free trial on the Starter tier. No credit card required. After the trial, choose a paid plan to continue.

Ready to build?

Get your API key in under a minute. Start with a free 7-day trial on the Starter tier.

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