The new statistics for Cardiff City Council have been revised from previous figures as the council has had to remove school playing fields unless the land is regularly available for public use.
Across the city, there are 174ha of recognised recreational space available to the public for sports and play compared to a target of 316ha.
The playing fields target is different from the published figures for green space in Cardiff — which include everything from cemeteries to wooded areas, lakes, ponds, scrubland and grass verges.
A spokesman said by using figures for all green areas in the city, Cardiff was one of the best cities in the UK for open space. He said a 2005 assessment showed Cardiff had a total of 47.9sq m of green space for each of its 321,000 residents — above the UK average of 36.2sq m.
He said: "Sheffield, which considers itself to have the most green space per person relative to any other city in the UK, had 49.3sq m per person — so Cardiff can class itself as being within the top echelon of green cities within the UK."
Playing fields organisation Fields in Trust development officer Rhodri Edwards said despite the city council's pride in its parklands, the organisation was concerned at the amount of recreation space that was under threat.
He said: "We appreciate that in established urban areas with established housing stock it is difficult to achieve the standard. But if there's an acknowledged shortfall in wards then surely that would be a stop on any further development, but you still see it happening.
"This is cropping up all over the city and this is something our organisation is concerned about and we will be looking to comment in all consultations that we can."
Subscribe to Horticulture Week for more news, more in-depth features and more technical and market info.