Photon Engine

Photon Engine (Exit Games) builds cross-platform multiplayer game networking backends - Photon Fusion, Photon Quantum, Photon Unity Networking (PUN), Photon Voice, Photon Chat, and the legacy Photon Bolt - all layered on the proprietary Photon Realtime transport protocol. Photon's core product is protocol-first and SDK-first, not REST-first - game clients exchange a custom binary message format (operation requests, operation responses, and events) with Name Server, Master Server, and Game Server roles, over UDP or TCP by default and, importantly, over WebSocket (ws:// unsecured, wss:// secured on port 443) as a first-class documented transport for WebGL and browser-hosted clients. Photon's own hosted surface exposes no general-purpose callable REST API for gameplay; the only genuinely HTTP surfaces are outbound - Room Lifecycle WebHooks (Photon POSTs room/join/leave/event/property/close notifications to a developer-hosted URL) and the Custom Authentication webservice contract (Photon calls out to a developer-hosted HTTP(S) endpoint to validate client tokens before allowing a connection). Pricing and account management are handled through the Photon Cloud Dashboard web UI, not a documented public REST API.

Photon Engine publishes 3 APIs on the APIs.io network: Photon Realtime Transport Protocol, Custom Authentication API, and Room Lifecycle WebHooks API. Tagged areas include Gaming, Multiplayer, Realtime, Netcode, and Game Networking.

The Photon Engine catalog on APIs.io includes 1 event-driven AsyncAPI specification and 1 Spectral governance ruleset.

Photon Engine’s developer surface includes documentation and 9 more developer resources.

42.8/100 developing ▬ flat Agent 23/100 agent aware Full breakdown ↓
scored 2026-08-05 · rubric v0.9.1
AccessFreemium
9 APIs
GamingMultiplayerRealtimeNetcodeGame NetworkingWebSocketBinary Protocol

Kin Score

Kin Score Kin Score How this is scored →
scored 2026-08-05 · rubric v0.9.1
Composite quality — 42.8/100 · developing
Contract Quality 15.2 / 25
Developer Ergonomics 1.7 / 20
Commercial Clarity 7.9 / 20
Operational Transparency 4.8 / 13
Governance 5.7 / 12
Discoverability 7.4 / 10
Agent readiness — 23/100 · agent aware
Machine-Readable Contract 18 / 18
Agentic Access Contract 10 / 10
MCP Server 0 / 12
Machine-Readable Auth 0 / 10
Idempotency 0 / 9
Stable Error Semantics 0 / 8
Request/Response Examples 0 / 7
Rate-Limit Signaling 7 / 7
Typed Event Surface 6 / 6
Agent Skills 0 / 5
Well-Known Catalog 0 / 4
Consent & Bot Identity 0 / 3
A2A Agent Card 0 / 8
Dry-Run / Simulate Mode 0 / 4
Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. This rating is computed from github.com/api-evangelist/photonengine: open an issue to ask a question, or submit a pull request to add artifacts. Want it done for you? Prioritized profiling — $2,500 →

APIs 9

Individual APIs this provider publishes, each with its own machine-readable definition.

Photon Realtime Transport Protocol

The core Photon protocol - NOT a REST or JSON API. Clients connect through a Name Server to a Master Server (matchmaking/lobby) and then a Game Server (room gameplay), exchangin...

Photon PUN (Photon Unity Networking) API

Photon Unity Networking 2, the original high-level Unity multiplayer SDK layered over the Photon Realtime transport protocol (same binary messages, same UDP/TCP/WebSocket transp...

Photon Fusion Networking API

Photon's current-generation, high-level networking framework for Unity, supporting Shared Mode, Client-Host, and dedicated Server Mode topologies with state-authoritative simula...

Photon Quantum Deterministic Simulation API

Photon's deterministic, ECS-based simulation framework that ships player inputs (not state) across all clients in lockstep, re-simulating identically on every machine. Transport...

Photon Voice API

Cross-platform low-latency voice chat built directly on top of Photon Realtime - it inherits Realtime's matchmaking, rooms, and interest groups and streams Opus-encoded audio fr...

Photon Chat API

A separately billed Photon Cloud service (its own AppId type) for text messaging, presence, and friend lists, dedicated Chat Servers speaking the same Photon Realtime-style bina...

Photon Bolt (Legacy, Deprecated)

Legacy UDP-based Unity netcode product from Exit Games. No longer actively developed and not recommended for new projects - superseded by Photon Fusion. Documented here for comp...

Photon Engine Custom Authentication API

Endpoint Photon's server calls to validate a connecting client's credentials. You implement this; Photon is the caller.

Photon Engine Room Lifecycle WebHooks API

Endpoints Photon's Game Server calls (HTTP POST) at points in a room's lifecycle. You implement these; Photon is the caller.

Scroll for all 9

Pricing Plans 1

Published pricing tiers and plan structures.

Rate Limits 1

Documented rate limits and quota policies.

Photonengine Rate Limits

5 limits

RATE LIMITS

FinOps 1

Cost, billing, and metering signals for API financial operations.

Event Specifications 1

AsyncAPI definitions for this provider's event-driven and streaming APIs.

Photon Realtime Transport Protocol over WebSocket

AsyncAPI 2.6 description of Photon's **WebSocket transport** for the Photon Realtime binary protocol. Photon Realtime (and everything built on it - PUN, Fusion, Quantum, Voice, ...

ASYNCAPI

Spectral Rules 1

Spectral governance rulesets for linting and validating these APIs.

Photon Engine API Rules

6 rules · 1 errors 4 warnings 1 info

SPECTRAL

Security Posture 2

Authentication, domain security, vulnerability disclosure, and trust-center signals.

Photonengine Domain Security

TLSv1.3 · DMARC

SECURITY

Photonengine Vulnerability Disclosure

security.txt · contact published

SECURITY

Agentic Access 1

Recommended x-agentic-access execution contracts for AI agents.

Photonengine Agentic Access

8 operations · 7 acting · 1 human-in-the-loop

8 operations · 7 acting

AGENTIC

Resources

Documentation 1

Reference material describing how the API behaves

Agent Surfaces 1

MCP servers, agent skills, and machine-readable catalogs

Build 1

SDKs, sample code, and the tooling you integrate with

Access & Security 2

Authentication, authorization, and security posture

Operate 1

Status, limits, changes, and where to get help

Commercial 2

Pricing, plans, and the legal terms of use

Company 2

The organization behind the API

Source (apis.yml)

apis.yml Raw ↑
aid: photonengine
url: https://raw.githubusercontent.com/api-evangelist/photonengine/refs/heads/main/apis.yml
name: Photon Engine
kind: company
description: Photon Engine (Exit Games) builds cross-platform multiplayer game networking backends - Photon Fusion, Photon
  Quantum, Photon Unity Networking (PUN), Photon Voice, Photon Chat, and the legacy Photon Bolt - all layered on the proprietary
  Photon Realtime transport protocol. Photon's core product is protocol-first and SDK-first, not REST-first - game clients
  exchange a custom binary message format (operation requests, operation responses, and events) with Name Server, Master Server,
  and Game Server roles, over UDP or TCP by default and, importantly, over WebSocket (ws:// unsecured, wss:// secured on port
  443) as a first-class documented transport for WebGL and browser-hosted clients. Photon's own hosted surface exposes no
  general-purpose callable REST API for gameplay; the only genuinely HTTP surfaces are outbound - Room Lifecycle WebHooks
  (Photon POSTs room/join/leave/event/property/close notifications to a developer-hosted URL) and the Custom Authentication
  webservice contract (Photon calls out to a developer-hosted HTTP(S) endpoint to validate client tokens before allowing a
  connection). Pricing and account management are handled through the Photon Cloud Dashboard web UI, not a documented public
  REST API.
accessModel:
  pricing: freemium
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Freemium
  confidence: medium
  source:
  - plans
  generated: '2026-07-22'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/photonengine.png
tags:
- Gaming
- Multiplayer
- Realtime
- Netcode
- Game Networking
- WebSocket
- Binary Protocol
created: '2026-07-03'
modified: '2026-07-03'
specificationVersion: '0.19'
apis:
- aid: photonengine:photonengine-realtime-transport-api
  name: Photon Realtime Transport Protocol
  tags:
  - Realtime
  - Binary Protocol
  - UDP
  - TCP
  - WebSocket
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  humanURL: https://doc.photonengine.com/realtime/current/getting-started/realtime-intro
  baseURL: wss://ns.exitgames.com:443
  properties:
  - url: https://doc.photonengine.com/realtime/current/getting-started/realtime-intro
    type: Documentation
  - url: https://doc.photonengine.com/realtime/current/reference/binary-protocol
    type: APIReference
  - url: https://doc.photonengine.com/realtime/current/connection-and-authentication/secure-networks
    type: Documentation
  - url: asyncapi/photonengine-asyncapi.yml
    type: AsyncAPI
  description: The core Photon protocol - NOT a REST or JSON API. Clients connect through a Name Server to a Master Server
    (matchmaking/lobby) and then a Game Server (room gameplay), exchanging a proprietary binary message format (operation
    requests, operation responses, and events framed inside eNet-style commands) over UDP (reliable/unreliable), TCP, or WebSocket.
    WebSocket is a first-class documented transport - clients set ConnectionProtocol to WebSocket or WebSocketSecure and connect
    with ws:// on port 80 or wss:// on port 443 (9090/19090 for self-hosted/Cloud Master listeners) - used primarily for WebGL
    and browser-hosted game clients.
- aid: photonengine:photonengine-pun-api
  name: Photon PUN (Photon Unity Networking) API
  tags:
  - PUN
  - Unity
  - Legacy
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  humanURL: https://doc.photonengine.com/pun/current/getting-started/pun-intro
  baseURL: wss://ns.exitgames.com:443
  properties:
  - url: https://doc.photonengine.com/pun/current/getting-started/pun-intro
    type: Documentation
  - url: https://doc-api.photonengine.com/en/pun/current/
    type: APIReference
  description: Photon Unity Networking 2, the original high-level Unity multiplayer SDK layered over the Photon Realtime transport
    protocol (same binary messages, same UDP/TCP/WebSocket transports). Still supported for existing projects; Photon recommends
    Fusion or Quantum for new projects.
- aid: photonengine:photonengine-fusion-api
  name: Photon Fusion Networking API
  tags:
  - Fusion
  - Netcode
  - State Authoritative
  - Unity
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  humanURL: https://doc.photonengine.com/fusion/current/getting-started/fusion-intro
  baseURL: wss://ns.exitgames.com:443
  properties:
  - url: https://doc.photonengine.com/fusion/current/getting-started/fusion-intro
    type: Documentation
  - url: https://doc-api.photonengine.com/en/fusion/current/
    type: APIReference
  description: Photon's current-generation, high-level networking framework for Unity, supporting Shared Mode, Client-Host,
    and dedicated Server Mode topologies with state-authoritative simulation. Runs its own tick/prediction layer on top of
    the Photon Realtime transport protocol; not a REST API.
- aid: photonengine:photonengine-quantum-api
  name: Photon Quantum Deterministic Simulation API
  tags:
  - Quantum
  - ECS
  - Deterministic
  - Lockstep
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  humanURL: https://doc.photonengine.com/quantum/current/manual/introduction
  baseURL: wss://ns.exitgames.com:443
  properties:
  - url: https://doc.photonengine.com/quantum/current/manual/introduction
    type: Documentation
  - url: https://doc.photonengine.com/quantum/current/manual/webhooks
    type: Documentation
  description: Photon's deterministic, ECS-based simulation framework that ships player inputs (not state) across all clients
    in lockstep, re-simulating identically on every machine. Transport is the shared Photon Realtime protocol (UDP/TCP/WebSocket);
    Quantum also supports the same Room Lifecycle WebHooks as Realtime/Fusion.
- aid: photonengine:photonengine-voice-api
  name: Photon Voice API
  tags:
  - Voice
  - Audio
  - Opus
  - VoIP
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  humanURL: https://doc.photonengine.com/voice/current/getting-started/voice-intro
  baseURL: wss://ns.exitgames.com:443
  properties:
  - url: https://doc.photonengine.com/voice/current/getting-started/voice-intro
    type: Documentation
  - url: https://doc-api.photonengine.com/en/voice/current/
    type: APIReference
  description: Cross-platform low-latency voice chat built directly on top of Photon Realtime - it inherits Realtime's matchmaking,
    rooms, and interest groups and streams Opus-encoded audio frames as Realtime events; no independent transport or REST
    surface of its own.
- aid: photonengine:photonengine-chat-api
  name: Photon Chat API
  tags:
  - Chat
  - Messaging
  - Presence
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  humanURL: https://doc.photonengine.com/chat/current/getting-started/chat-intro
  baseURL: wss://ns.exitgames.com:443
  properties:
  - url: https://doc.photonengine.com/chat/current/getting-started/chat-intro
    type: Documentation
  - url: https://doc-api.photonengine.com/en/chat/current/
    type: APIReference
  description: A separately billed Photon Cloud service (its own AppId type) for text messaging, presence, and friend lists,
    dedicated Chat Servers speaking the same Photon Realtime-style binary protocol over UDP/TCP/WebSocket - not a REST or
    JSON chat API.
- aid: photonengine:photonengine-bolt-api
  name: Photon Bolt (Legacy, Deprecated)
  tags:
  - Bolt
  - Legacy
  - Deprecated
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  humanURL: https://doc.photonengine.com/bolt/current/getting-started/bolt-intro
  baseURL: wss://ns.exitgames.com:443
  properties:
  - url: https://doc.photonengine.com/bolt/current/getting-started/bolt-intro
    type: Documentation
  description: Legacy UDP-based Unity netcode product from Exit Games. No longer actively developed and not recommended for
    new projects - superseded by Photon Fusion. Documented here for completeness since it remains listed among Photon's historical
    SDKs (PUN, Fusion, Quantum, Voice, Chat, Bolt).
- aid: photonengine:photonengine-custom-authentication-api
  name: Photon Engine Custom Authentication API
  description: Endpoint Photon's server calls to validate a connecting client's credentials. You implement this; Photon is
    the caller.
  humanURL: https://doc.photonengine.com/realtime/current/getting-started/realtime-intro
  baseURL: wss://ns.exitgames.com:443
  tags:
  - Custom Authentication
  properties:
  - type: OpenAPI
    url: openapi/photonengine-custom-authentication-api-openapi.yml
  - type: Documentation
    url: https://doc.photonengine.com/realtime/current/gameplay/web-extensions/webhooks
  - type: Documentation
    url: https://doc.photonengine.com/server/current/applications/loadbalancing/webhooks
  - type: Documentation
    url: https://doc.photonengine.com/realtime/current/connection-and-authentication/authentication/custom-authentication
- aid: photonengine:photonengine-room-lifecycle-webhooks-api
  name: Photon Engine Room Lifecycle WebHooks API
  description: Endpoints Photon's Game Server calls (HTTP POST) at points in a room's lifecycle. You implement these; Photon
    is the caller.
  humanURL: https://doc.photonengine.com/realtime/current/getting-started/realtime-intro
  baseURL: wss://ns.exitgames.com:443
  tags:
  - Room Lifecycle WebHooks
  properties:
  - type: OpenAPI
    url: openapi/photonengine-room-lifecycle-webhooks-api-openapi.yml
  - type: Documentation
    url: https://doc.photonengine.com/realtime/current/gameplay/web-extensions/webhooks
  - type: Documentation
    url: https://doc.photonengine.com/server/current/applications/loadbalancing/webhooks
  - type: Documentation
    url: https://doc.photonengine.com/realtime/current/connection-and-authentication/authentication/custom-authentication
common:
- type: AgenticAccess
  url: agentic-access/photonengine-agentic-access.yml
- type: VulnerabilityDisclosure
  url: security/photonengine-vulnerability-disclosure.yml
- type: DomainSecurity
  url: security/photonengine-domain-security.yml
- type: GitHubOrganization
  url: https://github.com/exitgames
- type: LinkedIn
  url: https://www.linkedin.com/company/photon-engine
- type: Website
  url: https://www.photonengine.com
- type: Documentation
  url: https://doc.photonengine.com
- type: Plans
  url: plans/photonengine-plans-pricing.yml
- type: RateLimits
  url: rate-limits/photonengine-rate-limits.yml
- type: FinOps
  url: finops/photonengine-finops.yml
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com