Excluding foreign travel, the near two-week huddle left a carbon footprint of 9,200 tonnes of carbon dioxide equivalent (tCO2e), chief event organiser Pierre-Henri Guignard told journalists in Paris.
This was equal to the carbon footprint of about 800 French people over a one-year period, and less than half the 21,000 tonnes organisers had expected.
"We went above and beyond what the United Nations expect of us," said Guignard.
The Paris event, dubbed COP21 for the 21st Conference of Parties, fared better than many of its predecessors, including COP15 in Copenhagen in 2009, which failed in its mission to yield a global climate pact.
More From This Section
Paris' footprint grows to 43,000 tCO2e with transport emissions for getting everyone to Paris, added Guignard.
Some 35,000 people were accredited as conference participants, with another 32,000 day visitors attending side events.
Like previous conference hosts, France intends to "offset" or cancel out emissions by financing carbon-reduction programmes in the developing world, at a price of about USD 11 per tonne of CO2e, Guignard said.
Much of the long-distance travel emissions had already been offset or cancelled out by delegates' countries of origin.
Under UN agreement, the host of the yearly climate COP (conference of parties) undertakes to make the event "climate neutral" by reducing emissions as much as possible.
The nations of the world agreed in Paris in December to limit average global warming to no more than two degrees Celsius over pre-Industrial Revolution levels.
Countries submitted pledges to curb emissions from burning coal, oil and gas which are blamed for warming the planet -- already estimated to be about 1.0 C hotter.