This page provides a centralized reference for the technical limits, project quotas, and usage policies that apply to Remote Config.
Project-wide quotas
The following table outlines the maximum allowable thresholds for template resources across your entire Firebase project. These limits ensure optimal template evaluation performance and backend stability.
| Resource | Limit | Details |
| Parameters | 3,000 per template type | 3,000 for client templates and 3,000 for server templates. |
| Conditions | 2,000 per project | Shared across all templates. |
| Template Versions | 300 per template type | Includes deleted versions. Versions beyond this are automatically purged. Template versions older than 90 days are automatically deleted. |
| Experiments & Rollouts | 24 combined | Total count of running A/B tests and feature rollouts can't exceed 24 per project. |
| Real-time Connections | 20,000,000 (20 million) per project | See Real-time limits. |
Parameter and key constraints
The following table defines the character length and content restrictions for parameter keys, values, and group names. Adhering to these constraints prevents configuration publish errors and client schema mismatches.
| Element | Limit | Details |
| Key Length | 256 characters | Must start with _ or A-Z, a-z. Can include numbers. |
| Total Value Content | 1,000,000 characters | The sum of all parameter value strings in a project. |
| Group Name Length | 256 characters | Applies to parameter group labels in the Firebase console. |
Condition and targeting limits
The following table specifies the limits for custom targeting rules, signal attributes, and conditional syntax. These boundaries maintain fast rule evaluation when serving configurations to individual client instances.
| Element | Limit | Details |
| Custom Signals | 100 per app instance | Max 100 unique signals can be set on a single device. |
| Custom Signal Key | 250 characters | Max length for the attribute name. |
| Custom Signal Value | 500 characters | Max length for the attribute value (250 if using Regex). |
| Installation IDs | 50 per condition | Max number of IDs allowed in an "Installation ID" rule. |
| Condition Name | 100 characters | Name used to identify the condition in the Firebase console or API. |
| Regular expression syntax | RE2 format | All regular expressions must follow RE2 syntax |
Real-time limits
The following table details the concurrent open connection limits when using Real-time Remote Config. These quota boundaries ensure stable real-time client update distribution across global client instances.
| Resource | Limit | Details |
| Concurrent open connections | 20,000,000 (20 million) per project | If exceeded, new connection requests are rejected and the client SDK automatically falls back to standard periodic fetching. This limit is temporarily suspended while a newly published template is actively propagating so all connected clients receive updates. |
Operational policies
To ensure a safe and compliant user experience, adhere to the following policies:
- Don't use Remote Config to make app updates that should require a user's authorization. This could cause your app to be perceived as untrustworthy.
- Don't store confidential data in Remote Config parameter keys or parameter values. Remote Config data is encrypted in transit, but end users can access any default or fetched Remote Config parameter that is available to their app instance.
- Don't attempt to circumvent the requirements of your app's target platform using Remote Config.