API Design · Senior · Question 68 of 75

When might an API offer Protobuf or another binary format in addition to JSON?

✓Correct answer: For high-volume or bandwidth-sensitive clients (mobile, IoT, internal services), negotiated via Accept, while keeping JSON for general use
2Never, JSON is the only valid API format
3Always, replacing JSON completely

Explanation

Binary formats save bytes and parsing time but are harder to debug and need schema distribution.

Further reading

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