256 MB from the REST API; 16 MB from the SDKs . The total data in each write operation should be less than 256 MB. Multi-path updates are subject to the same size limitation. The total bytes written through simultaneous write operations on the database at any given time.
Read moreHow much free storage does Firebase give?
Cloud Firestore database is a recommended database of Firebase. It offers a total of 1GB free storage in the Spark plan.
Read moreIs Firebase suitable for large amount of data?
The real-time functions in Firebase are not only suited for, but designed for large data sets . The fact that records stream in real-time is perfect for this. Performance is, as with any large data app, only as good as your implementation.
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