JSON vs JSONB in PostgreSQL: I tested 1M rows to find out

Eugene — Sun, 12 Apr 2026 07:52:39 +0000

Recently I tried to resolve a recurring question in our team:

Is JSON or JSONB actually faster in PostgreSQL?

I couldn’t find a clear answer that matched real-world usage, so I ran my own benchmark.

Setup

I loaded 1 million records with identical data into both JSON and JSONB columns and tested common operations.

Hardware:
Dell PowerEdge R450
2x Intel Xeon Silver 4310 (24/48 cores @ 2.1GHz)

I intentionally used mid-range hardware so the differences would be easier to see.

What I tested

INSERT performance
Key-based search (data->>'field' = 'value')
Nested updates
Complex multi-condition queries
Array access (data->'items'[0])
Key existence (data ? 'key')
Path queries (data #> '{user,profile,name}')
Aggregations
Storage size

Results

Insert speed

JSON was faster:

JSON: 8.6s
JSONB: 11.3s

~31% difference, which makes sense - JSON is stored as plain text.

Query performance

This is where things got interesting.

JSONB was significantly faster across all read operations:

Simple key extraction → 6.2x faster
Nested field access → 7.6x faster
Array operations → 7.3x faster
Complex conditions → 9.1x faster

On average: ~7x faster

GIN indexes + binary format make a huge difference here.

Updates

For partial updates:

JSONB was ~71% faster

Storage

JSON: ~1200 MB
JSONB: ~888 MB

JSONB used ~26% less space, mainly due to key deduplication.

Key takeaway

If your workload is read-heavy (which is most backend systems):

JSONB pays for itself very quickly.

Even with slower inserts, the performance gain in queries dominates after relatively few operations.

One important detail

Operators like:

@>
?
?&

only work with JSONB.

Without them, efficient querying becomes very limited.

Repo

I published the full benchmark here:

https://github.com/ineron/postgresql-json-jsonb-benchmark

Includes:

SQL scripts
Python automation
Docker setup

Final thought

I expected JSONB to be faster, but not by this margin.

Curious if anyone has seen similar results in production?

Forem: Eugene