What Is metric_key?

Learn what metric_key means in growthepie and how metric_key differs from metric_id.

metric_key is the canonical identifier for a raw exported series in growthepie data. You see metric_key values directly in flat export rows such as txcount, daa, fees_paid_usd, fees_paid_eth, or gas_per_second.

Key Facts

• metric_key appears in flat row exports

• Some higher-level metrics map to one raw metric_key, such as txcount

• Some higher-level metrics map to multiple raw metric_key values, usually currency pairs such as USD and ETH

• metric_key is not the same thing as metric_id

metric_id vs metric_key

Term	Example	Used where
metric_id	fees	Rich detail paths such as metrics/chains/arbitrum/fees.json
metric_key	fees_paid_usd	Flat row payloads such as fundamentals.json

Example

The higher-level metric fees maps to two raw metric_key values:

• fees_paid_usd

• fees_paid_eth

FAQ

Why do some metrics have both USD and ETH keys?

Currency-denominated metrics often expose both USD and ETH series in the backend metric registry and in master.json.

Where do I find the mapping from metric_id to metric_key?

Use master.json.metrics. Each metric entry includes the canonical metric_keys array.

Related Pages

• Metric Reference Overview

• Endpoint: master.json