---
title: "Convert JSON to PostgreSQL"
description: "Convert JSON files to SQL for PostgreSQL in your browser: a CREATE TABLE with typed columns, then INSERT statements. Free, and your file is never uploaded."
canonical: https://intosql.com/json-to-postgresql
last_updated: 2026-10-15
---

# Convert JSON to PostgreSQL

Drop your JSON file to get a PostgreSQL script with CREATE TABLE and INSERT statements. Each column gets a type, and every fix is listed with its row and column.

## From JSON to PostgreSQL, column by column

The sample above, pedidos_2024.json, as IntoSQL writes it for PostgreSQL: what each column holds in the file, the type it gets and how its first value lands in the script.

| In the file | First value | Column | PostgreSQL type | In the script |
| --- | --- | --- | --- | --- |
| pedido | `000481` | `pedido` | `text` | `'000481'` |
| cliente | `Peña Muñoz` | `cliente` | `text` | `'Peña Muñoz'` |
| fecha | `2024-02-03T10:15:00Z` | `fecha` | `timestamptz` | `'2024-02-03 10:15:00+00:00'` |
| total | `1234.5` | `total` | `numeric(6,2)` | `1234.5` |
| pagado | `true` | `pagado` | `boolean` | `TRUE` |
| notas | `` | `notas` | `text` | `NULL` |

## Load the script into PostgreSQL

The download is a plain .sql file. Run it with PostgreSQL's own tools.

### PostgreSQL

```shell
psql -v ON_ERROR_STOP=1 -d mydb -f pedidos_2024.postgresql.sql
```

ON_ERROR_STOP makes psql stop at the first error. The script runs in one transaction, so a failed load leaves the database as it was. In pgAdmin or DBeaver, open the script in a query window and run it.

Without a script:

```shell
intosql load pedidos_2024.json --into postgres://user@localhost/mydb
```

## What IntoSQL reads in JSON files

- The file can be an array of objects, an object that holds that array under a key such as data, or one object per line (NDJSON).
- Each key becomes a column. Objects and arrays inside a value are kept as JSON text.
- Numbers keep their exact digits, and ISO 8601 dates become dates or timestamps.

## What to know about PostgreSQL

- Decimals keep their exact digits as numeric(p,s), and dates with an offset become timestamptz.
- PostgreSQL text can't hold the NUL character, so it is removed from the values that have one.
- The script runs in one transaction, so a load that fails leaves nothing half done.

### How each kind of value is stored in PostgreSQL

| Value | PostgreSQL |
| --- | --- |
| Yes and no | `boolean` |
| Whole numbers | `integer` |
| Large whole numbers | `bigint` |
| Decimals | `numeric(p,s)` |
| Floating-point numbers | `double precision` |
| Dates | `date` |
| Times of day | `time` |
| Dates with a time | `timestamp` |
| Dates with a time and offset | `timestamptz` |
| Text | `text` |

## Questions about JSON to PostgreSQL

### How do I convert JSON to PostgreSQL?

Drop your file on the converter at the top of this page. It finds the header, reads every value and writes the PostgreSQL script, listing each fix it made. Download the script and run it with psql.

### What shape does the JSON file need?

An array of objects, an object that holds that array under a key such as data, or one object per line (NDJSON). Each key becomes a column.

### Which PostgreSQL types does it use?

Yes and no values become boolean, whole numbers integer, decimals numeric(p,s), dates date, dates with a time timestamp and text text. Sizes come from the longest value in each column.

### Does it keep leading zeros in PostgreSQL?

Yes. A code such as 000481 stays text, so PostgreSQL stores it as text and the script writes it as '000481'.

### Can it load the data into PostgreSQL without a script?

Yes, with IntoSQL Pro. The desktop app and the command line connect to PostgreSQL and load the rows straight in, creating the table first.

### How big can the JSON file be?

NDJSON, one object per line, is read as it streams in, so files of several gigabytes work in the browser. A JSON document is read whole, so its limit is the memory the browser gives this page. The desktop app and the command line take files of any size.

## JSON into other databases

- [Convert JSON to SQL](https://intosql.com/json-to-sql)
- [Convert JSON to MySQL](https://intosql.com/json-to-mysql)
- [Convert JSON to MariaDB](https://intosql.com/json-to-mariadb)
- [Convert JSON to SQLite](https://intosql.com/json-to-sqlite)
- [Convert JSON to SQL Server](https://intosql.com/json-to-sql-server)
- [Convert JSON to Oracle](https://intosql.com/json-to-oracle)

## Other files into PostgreSQL

- [Convert Excel to PostgreSQL](https://intosql.com/excel-to-postgresql)
- [Convert CSV to PostgreSQL](https://intosql.com/csv-to-postgresql)