Prebid Integration🔗

51Degrees enriches OpenRTB bid requests with three streams of data: Device Detection properties, the 51Did probabilistic device identifier, and IP Intelligence location signals. Together they let buyers target and value impressions more accurately, and recognise the same device across requests without cookies.

See it work. The interactive Prebid.js demo fires contemporary device samples against random public IPs and shows the bid object populate live against cloud.51degrees.com.

What the Integration Delivers🔗

Enrichment stream	Prebid.js RTD Module (client-side)	Prebid Server (server-side)
Device Detection - make, model, OS, screen, device ID	✅	✅
51Did - probabilistic device identifier	✅	-
IP Intelligence - IP address and geo	✅	-

The client-side RTD module delivers all three streams. The server-side Prebid Server modules currently deliver device detection only.

Implementation Options🔗

You can enrich bid requests in the browser or on your Prebid Server.

Client-Side: Prebid.js RTD Module🔗

Use this when you want the full enrichment set (device, 51Did, IP Intelligence) and maximum device-detection accuracy. The module runs in the user's browser, can read JavaScript APIs for precise device identification (best for distinguishing Apple models), and calls cloud.51degrees.com to fetch the data.

Setup: Prebid.js RTD Module Documentation

Resource Key properties. Generate the key with the Cloud Configurator. To populate every field the RTD module writes, include:

Device Detection (device.*): DeviceId, DeviceType, HardwareVendor, HardwareName, HardwareNamePrefix, HardwareNameVersion, HardwareModel, PlatformName, PlatformVersion, ScreenPixelsHeight, ScreenPixelsWidth, ScreenPixelsPhysicalHeight, ScreenPixelsPhysicalWidth, ScreenInchesHeight, ScreenInchesWidth, PixelRatio, ThirdPartyCookiesEnabled.
IP Intelligence (device.ip, device.geo.*): Latitude, Longitude, CountryCode3, Iso31662Lvl4, ZipCode, TimeZoneOffset, AccuracyRadiusMin, LocationConfidence.
51Did (user.eids): IdProbLic, IdProbGlobal. Issuing the 51Did for standard or personalized usage also requires a Special license key on the Resource Key (see the 51Did section below).

Server-Side: Prebid Server (Java and Go)🔗

Use this when you need faster response times or want to centralize detection logic. Prebid Server currently adds device detection properties only. Both the Java and Go implementations share a single Prebid.org module documentation page: Prebid Server 51Degrees Module Documentation

Enrichment Streams🔗

Device Properties🔗

The modules detect the device from HTTP headers (and, client-side, JavaScript signals) and map the result onto the OpenRTB device object: make, model, os, osv, hwv, h, w, pxratio, ppi, and devicetype. A 51Degrees device ID is attached in an ext field that links to 250+ further properties in the property dictionary.

The device-ID field name currently differs by integration:

Integration	Device-ID field	Extras
Prebid.js RTD Module	`device.ext.fod.deviceId`	`device.ext.fod.tpc` (whether third-party cookies are enabled in this browser session, 1 or 0)
Prebid Server (Java and Go)	`device.ext.fiftyonedegrees_deviceId`	-

The RTD module additionally reports whether third-party cookies are enabled in the current browser session. The ThirdPartyCookiesEnabled property is mapped to device.ext.fod.tpc as 1 (third-party cookies are enabled in this browser session) or 0 (disabled), and is omitted when this is unknown. See Third-Party Cookies Detection for how the signal is detected.

For the full field-by-field mapping between OpenRTB and 51Degrees properties, see OpenRTB Mappings.

51Did🔗

The 51Did is a signed, probabilistic 51Degrees device identifier (a base64 OWID envelope). It lets a buyer reconcile the same device across requests independently of cookies or IDFA, because it is derived from the device, IP, and declared usage purpose rather than from stored state. See 51Did (51Degrees Identifier) for the identifier-versus-value distinction and the licensing model.

The RTD module surfaces the 51Did in the OpenRTB 2.6 user.eids array as a single source entry:

{

"user": {

"eids": [

{

"inserter": "51degrees.com",

"source": "51d.es",

"mm": 5,

"uids": [

{ "id": "AzUxZC5lcwBzGTMAJQAAAAHWTQ...", "atype": 1 },

{ "id": "AzUxZC5lcwCxHzMAJQAAAAHWTQ...", "atype": 1 }

],

"ext": { "tdl": ["https://tdl.51degrees.com/..."] }

}

]

}

mm: 5 marks the match method as probabilistic.
The two uids are the license-tier identifier (idproblic) and the global-tier identifier (idprobglobal), in that order.
ext.tdl is emitted only when a transparency-and-disclosure URL is configured (the tdlUrl module parameter); it is omitted otherwise.

The 51Did is delivered by the RTD module only. Issuing it for standard or personalized usage purposes requires a Special license key on the Resource Key; the non-marketing purpose is available in the free tier. See 51Did (51Degrees Identifier) for licensing and PMP (Preference Management Platform) for capturing the user's marketing preference that feeds id.usage.

IP Intelligence🔗

From the request IP the RTD module adds the IP address and, when confident, an approximate location to the device object:

device.ip and device.ipv6 are always set when available.
device.geo.* (lat, lon, country as ISO-3166-1 alpha-3, region as ISO-3166-2, zip, utcoffset, accuracy) is set only when location confidence is high or medium. device.geo.type is 2 (IP-derived) and device.geo.ipservice is 511 (high confidence) or 512 (medium).

This stream provides IP and geo only. Connection type, carrier/ISP, ASN, and MCC-MNC are not surfaced in the bid object - contact us if you need them. For the full OpenRTB Geo mapping see OpenRTB Mappings. IP Intelligence in the bid stream is delivered by the RTD module only; see IP Intelligence Overview for the data itself.

Enriched Bid Request Examples🔗

Client-side (RTD module) - full enrichment🔗

{

"device": {

"make": "Apple",

"model": "iPhone 17 Pro Max",

"os": "iOS",

"osv": "18.6",

"w": 1320,

"h": 2868,

"pxratio": 3.0,

"ppi": 460,

"devicetype": 1,

"ip": "185.69.144.0",

"geo": {

"lat": 51.5,

"lon": -0.12,

"country": "GBR",

"region": "GB-ENG",

"zip": "EC1A",

"utcoffset": 0,

"accuracy": 50000,

"type": 2,

"ipservice": 511

},

"ext": {

"fod": {

"deviceId": "17595-131070-140777-18092",

"tpc": 1

}

},