---
obj: concept
website: https://bsonspec.org
wiki: https://en.wikipedia.org/wiki/BSON
---

# BSON
BSON, short for Bin­ary [JSON](JSON.md), is a bin­ary-en­coded seri­al­iz­a­tion of [JSON](JSON.md)-like doc­u­ments. Like [JSON](JSON.md), BSON sup­ports the em­bed­ding of doc­u­ments and ar­rays with­in oth­er doc­u­ments and ar­rays. BSON also con­tains ex­ten­sions that al­low rep­res­ent­a­tion of data types that are not part of the [JSON](JSON.md) spec. For ex­ample, BSON has a Date type and a BinData type. [MongoDB](../applications/development/MongoDB.md) uses BSON internally for storing the database.

BSON was de­signed to have the fol­low­ing three char­ac­ter­ist­ics:
- Lightweight: Keep­ing spa­tial over­head to a min­im­um is im­port­ant for any data rep­res­ent­a­tion format, es­pe­cially when used over the net­work.
- Traversable: BSON is de­signed to be tra­versed eas­ily. This is a vi­tal prop­erty in its role as the primary data rep­res­ent­a­tion for Mon­goDB.
- Efficient: En­cod­ing data to BSON and de­cod­ing from BSON can be per­formed very quickly in most lan­guages due to the use of C data types.