Meter Features

Meter features are the most powerful feature type in Fluxrate. They combine usage tracking with entitlement enforcement, letting you both bill for usage and gate access when limits are hit.

How Meter Features Work

When you create a meter feature, Fluxrate automatically creates:

A Feature (the entitlement definition)
A corresponding Meter (the usage tracking engine)

The meter has a unique meter_token that your backend uses to send usage events.

Creating a Meter Feature

Dashboard
API

Go to Features in the sidebar
Click Add Feature
Select Meter as the type
Configure the meter settings and click Create

curl -X POST https://api.fluxrate.co/api/v1/features \
  -H "Content-Type: application/json" \
  -H "Cookie: access_token=<token>" \
  -d '{
    "name": "API Calls",
    "lookup_key": "api_calls",
    "description": "Number of API requests made",
    "type": "meter",
    "meter_name": "api_calls",
    "property_name": "call_count",
    "aggregation_type": "SUM",
    "unit": "calls"
  }'

Request Fields

Field	Required	Description
`name`	✅	Display name for the feature
`lookup_key`	✅	Unique identifier (slug) for this feature
`meter_name`	✅	Internal meter identifier (must be unique per org)
`property_name`	✅	The event payload property to read for aggregation
`aggregation_type`	✅	How to aggregate: `SUM`, `MAX`, `UNIQUE_COUNT`, `LAST`
`unit`		Display unit (e.g., “calls”, “GB”, “tokens”)
`description`		Human-readable description

Aggregation Types

SUM

Adds up all values received in the billing period. Best for: API calls, data transferred, messages sent, compute minutes.

// Events
{ "property_name": "1" }  // call 1
{ "property_name": "1" }  // call 2
{ "property_name": "5" }  // bulk operation

// Result: SUM = 7

MAX

Takes the highest single value observed during the period. Best for: Peak concurrent connections, high-water mark measurements.

// Events
{ "property_name": "10" }  // 10 concurrent connections
{ "property_name": "25" }  // peak: 25
{ "property_name": "15" }

// Result: MAX = 25

UNIQUE_COUNT

Counts the number of distinct values of a property. Best for: Monthly active users, unique devices, distinct API consumers.

// Events (counting unique user_ids)
{ "user_id": "user_a" }
{ "user_id": "user_b" }
{ "user_id": "user_a" }  // duplicate - not counted again

// Result: UNIQUE_COUNT = 2

For UNIQUE_COUNT meters, send the value to count as the metadata.user_id field. The SDK endpoint handles this mapping automatically.

LAST

Takes the most recent value received. Best for: Current storage usage, current seat count (snapshot billing).

// Events received over time
{ "property_name": "50" }  // at 10:00
{ "property_name": "75" }  // at 14:00
{ "property_name": "60" }  // at 18:00

// Result: LAST = 60

Usage Filters

Meter features support filters to segment events. For example, track API calls only from specific regions or versions:

curl -X POST https://api.fluxrate.co/api/v1/features \
  -H "Content-Type: application/json" \
  -H "Cookie: access_token=<token>" \
  -d '{
    "name": "Premium API Calls",
    "lookup_key": "premium_api_calls",
    "type": "meter",
    "meter_name": "premium_api_calls",
    "property_name": "call_count",
    "aggregation_type": "SUM",
    "filters": [
      {
        "key": "tier",
        "values": ["premium", "enterprise"]
      }
    ]
  }'

Filter Rules

Maximum 5 filters per meter
Each filter supports up to 15 values
Values are matched exactly (strings)
Filter keys cannot be added or removed after creation — only values can be updated

Setting Entitlement Limits

When attaching a meter feature to a plan, configure the usage limit:

# Unlimited usage
{
  "feature_id": "<feature_id>",
  "is_enabled": true,
  "is_unlimited": true
}

# Limited usage
{
  "feature_id": "<feature_id>",
  "is_enabled": true,
  "usage_limit": 10000,
  "usage_reset_period": "month",
  "is_soft_limit": false
}

Option	Description
`is_unlimited: true`	No usage cap — just track and bill
`usage_limit`	Maximum units allowed in `usage_reset_period`
`usage_reset_period`	When the counter resets: `day`, `week`, `month`, `year`
`is_soft_limit`	`true` = warn but don’t block; `false` = hard block at limit

Use soft limits in SaaS products where you want to upsell users who exceed their plan, rather than hard-blocking them.

Get Started

Product Guide

Developer Guides

How Meter Features Work

Creating a Meter Feature

Request Fields

Aggregation Types

SUM

MAX

UNIQUE_COUNT

LAST

Usage Filters

Filter Rules

Setting Entitlement Limits

​How Meter Features Work

​Creating a Meter Feature

​Request Fields

​Aggregation Types

​SUM

​MAX

​UNIQUE_COUNT

​LAST

​Usage Filters

​Filter Rules

​Setting Entitlement Limits

How Meter Features Work

Creating a Meter Feature

Request Fields

Aggregation Types

SUM

MAX

UNIQUE_COUNT

LAST

Usage Filters

Filter Rules

Setting Entitlement Limits