13,883 civilians died in Ukraine as a result of Russian invasion between 24 Feb. 2022 and 31 July 2025 according to United Nations. It's really easy to Google it.
On August 29, President of Mariupol Television, volunteer and civil activist Mykola Osychenko said to Dnipro TV that, according to the insider information, 87,000 deaths have been currently documented in morgues in Mariupol. Besides, 26,750 bodies are buried in mass graves, and many more are buried in the yards of the apartment blocks and private houses, or still under the rubble.[326]
In early November, Ukraine stated that at least 25,000 civilians had been killed in Mariupol.[46][47] In late December, based on the discovery of 10,300 new mass graves, the Associated Press estimated that the true death toll may be up to three times that figure.[327] The Uppsala Conflict Data Program estimates of the total death toll resulting from the siege range from 27,000 to 88,000 fatalities, most of them civilians.[49]
just to put things into perspective, this siege lasted less than 3 months
"According to a 2023 study by Human Rights Watch and two other organizations, there were at least 8,034 excess deaths in Mariupol between March 2022 and February 2023."