# Population (1 January) — Kocaeli (NUTS-3 TR421)

Population (1 January) — Kocaeli (NUTS-3 TR421) was 2,130,006 persons in 2025, up 1.3% from 2024.
That is the highest reading since the series began in 2001.
Over the past ten years it has ranged from 1,722,795 persons (2015) to 2,130,006 persons (2025), averaging 1,947,182 persons.

- Source agency: Eurostat (Statistical Office of the European Union)
- Makrognosis code: `TR-421.POP.A.NSA`
- Frequency: annual
- Units: persons
- Coverage: 2001-01-01 to 2025-01-01 (25 observations)
- Page: https://makrognosis.robomacro.com/data/turkey/population-1-january-kocaeli-nuts-3-tr421

## Recent data

| Period | Value |
|---|---:|
| 2025 | 2,130,006 persons |
| 2024 | 2,102,907 persons |
| 2023 | 2,079,072 persons |
| 2022 | 2,033,441 persons |
| 2021 | 1,997,258 persons |
| 2020 | 1,953,035 persons |
| 2019 | 1,906,391 persons |
| 2018 | 1,883,270 persons |
| 2017 | 1,830,772 persons |
| 2016 | 1,780,055 persons |
| 2015 | 1,722,795 persons |
| 2014 | 1,676,202 persons |
| 2013 | 1,634,691 persons |
| 2012 | 1,601,720 persons |
| 2011 | 1,560,138 persons |
| 2010 | 1,522,408 persons |
| 2009 | 1,490,358 persons |
| 2008 | 1,437,926 persons |
| 2007 | 1,403,154 persons |
| 2006 | 1,368,547 persons |
| 2005 | 1,334,747 persons |
| 2004 | 1,301,853 persons |
| 2003 | 1,270,134 persons |
| 2002 | 1,238,554 persons |

## API

```
curl -H "X-API-Key: $MAKROGNOSIS_KEY" \
  "https://makrognosis.robomacro.com/v1/series/TR-421.POP.A.NSA"

# Python
import requests
r = requests.get("https://makrognosis.robomacro.com/v1/series/TR-421.POP.A.NSA",
                 headers={"X-API-Key": KEY})
obs = r.json()["observations"]
```