What are the primary data types in MongoDB?

Updated May 1, 2026

Short answer

MongoDB supports BSON types like String, Integer, Boolean, Double, Array, Object, and Date.

Deep explanation

Specific types like ObjectId, Binary data, and Decimal128 are also supported for specialized needs.

Real-world example

Using NumberDecimal for financial transactions to avoid floating-point errors.

Common mistakes

Using Strings for dates instead of the native Date type.

Follow-up questions

What is Decimal128 used for?

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