Photon Quantum

Photon Quantum is a deterministic multiplayer framework for Unity games built around synchronized player input and rollback. It suits teams that need tight simulation control and can work within Photon’s cloud quotas or its higher-tier membership requirements. Its strongest case is the combination of rollback and extensible server logic; its main trade-off is that capacity, traffic and SDK access shape the choice of plan.

Overview

Quantum separates game simulation from Unity’s presentation layer, using Unity for editor tooling and the view while deterministic libraries handle simulation. Clients exchange inputs and predict other players’ actions; when a prediction is wrong, they restore and resimulate the game state. That model is aimed at games where consistent simulation matters more than simply synchronizing a changing state.

The documented simulation libraries cover math, 2D and 3D physics, navigation, animation and bots. Photon Realtime transport and Photon servers synchronize clocks and manage input latency. Matchmaking is supported, and transports include UDP, TCP, WebSocket and Secure WebSocket. Quantum is listed for sessions of up to 128 players.

Key features

Rollback simulation: Local prediction can keep play moving while inputs are in transit, with correction by restoring and resimulating when predictions diverge. This is useful for games that need deterministic outcomes, though it requires a team prepared to build around that simulation model.

Extensible server component: Teams can connect customer-hosted matchmaking, player services or referee simulations rather than treating Photon’s infrastructure as the entire backend.

Quantum 3 webhooks: Webhooks can control rooms, validate configuration and player data, and send full match replays to a configurable endpoint. That gives teams server-side hooks for validation and replay handling.

Cheat resistance: Photon says deterministic gameplay and input-only exchange help resist cheating; replay validation and server referee simulations are additional anti-cheat measures. These are design options, not a guarantee against cheating.

Plugin SDK access: The SDK enables creation and local testing of a custom Quantum server for Photon Enterprise Cloud, but requires Gaming Circle or Industries Circle membership. That access condition can be a significant obstacle for teams that need custom server work without those memberships.

Pricing

The free tiers are useful for prototyping and smaller games, but both cap concurrent users and monthly traffic, and neither includes a CCU burst. Development Only 20 CCU costs nothing and provides 20 connected users, 60.0 GB traffic per month, and development use only. Free 100 CCU costs nothing and allows one app per customer, games only, approximately 40k MAU and 0.3 TB traffic per month.

The paid 100 CCU plan costs $95 as a one-time purchase, billed one-time for 12 months. It retains the 100-user, one-app, games-only, approximately 40k MAU and 0.3 TB monthly traffic limits of the free 100 CCU tier, with no CCU burst. It suits a small production title with predictable traffic, but not one expecting spikes above its cap.

For more capacity, 500 CCU costs $125 a month and includes approximately 200k MAU, 1.5 TB traffic per month and CCU burst. 1000 CCU costs $250 a month, with approximately 400k MAU, 3.0 TB traffic and burst; 2000 CCU costs $500 a month, with approximately 800k MAU, 6.0 TB traffic and burst. These monthly plans fit games scaling beyond the free tiers, with the higher tiers trading higher recurring cost for more capacity and traffic.

Premium Cloud is $0.50 a month, invoiced based on monthly usage, with a $1,000 minimum fee per month. It has a 2,000 CCU minimum, includes 6.0 TB traffic, supports usage-based CCU auto-scaling and includes DDoS protection by default. The minimum commitment makes it a poor fit for small launches, but the included scaling and protection suit larger services. Enterprise Cloud has custom pricing and provides a dedicated managed cloud environment, unlimited titles, SLA, priority operations support, dedicated servers, server-authoritative logic via plug-ins and multi-layered DDoS protection.

Free plans include online documentation, samples, tutorials, video streams and help with account and billing matters. Gaming Circle offers premium development support; the Plugin SDK membership requirement is separate from the free-plan entry point.

Platforms

Supported platforms include Windows, macOS, Android, iOS, WebGL, Nintendo Switch, Xbox One, Xbox Series X|S, PS4 and PS5. A provided sample targets Unity WebGL and integrates CrazySDK from Crazy Games. Platform breadth makes Quantum relevant to teams shipping across desktop, mobile, browser and consoles, while Unity remains central to its editor and presentation workflow.

Who it's for

Quantum is best suited to Unity teams building deterministic multiplayer games that benefit from input prediction, rollback and the option to extend server behavior. It is less suitable for small projects that need generous uncapped production capacity, or teams that require the custom-server Plugin SDK but cannot meet its membership condition.

Pros and cons

Pro: Prediction and rollback provide a defined approach to correcting divergent simulation without exchanging full game states.

Pro: The documented libraries span physics, navigation, animation and bots, while server extensions and webhooks support custom services and match validation.

Pro: Free plans allow development or a small game to start without a plan fee.

Con: Free tiers have strict user and traffic limits, and do not allow CCU bursts.

Con: Premium Cloud carries a $1,000 minimum fee per month and a 2,000 CCU minimum.

Con: Creating and locally testing a custom Quantum server through the Plugin SDK requires Gaming Circle or Industries Circle membership.

Alternatives

Browse the Game Networking Middleware category to compare other networking options. Choose Photon Fusion for another freemium Photon option with a free 100 CCU tier. Photon Realtime is another freemium Photon offering, including a 20 CCU development tier. Consider Normcore if its free Public plan’s unlimited concurrent users and rooms suit the project. Colyseus offers an open-source self-hosted plan with no restrictions, making it an option for teams that want to run their own servers. FishNet is a free Unity networking solution with no CCU caps or CCU paywalls. Netcode for GameObjects is a free Unity package requiring a valid Unity account and license. Netick offers free server-authoritative state-sync networking for Unity. Mirror Networking is free and open source under MIT, with no paywalls or CCU costs.

Verdict

Choose Photon Quantum if your Unity game needs deterministic simulation, rollback and room to integrate custom server-side services. Its strongest advantage is a coherent input-driven model backed by broad simulation libraries and Photon infrastructure. Look elsewhere if low-cost uncapped capacity or unrestricted access to custom-server tooling is central to the project.