Keegan Jakovlevs, whose post on Facebook called for all British Muslims to be killed, has been jailed for a year.
The man had previously pleaded guilty to publishing material with the intention of stirring up religious hatred.
Wrexham man Jakovlev was sentenced at Mold Crown Court for the crime.
The 22-year-old posted his message shortly after the bombing at Manchester Arena on 22 May, according to prosecutors, and took it down shortly afterwards.
Salman Abedi killed 22 victims, including children, and injured 250 more, at an Ariana Grande concert when he detonated a homemade bomb as the crowds left the arena.
A spokesperson for the Crown Prosecution Service (CPS) said, “Jakovlevs’s Facebook message expressed sympathy for the families of those caught up in the bombing but then, using racist and offensive language, he called for every Muslim in the country to be killed.”
“The prosecution argued that Jakovlevs’s single message was particularly serious because it was posted so soon after the Manchester bombing when public emotions were running high.”
The CPS said the message was accessible, “at the very least”, to his 2,154 Facebook friends, but also to other members of the public.
“Overall, there was potential for it to have been seen by a very large number of people and for serious harm to have occurred in addition to the obvious fear and distress suffered by any member of the Muslim community who may have seen it,” added prosecutors.
Sue Hemming, head of the special crime and counter-terrorism division in the CPS, said that whilst no action was traced back to the post, Jakovlev’s “intention was clear”.
“After the Manchester attack, there were countless messages of support on social media for those affected but Keegan Jakovlevs chose to stir up religious hatred by calling for British Muslims to be indiscriminately killed,” she said.
“People should not assume they can hide on social media when stirring up hatred and violence. Where there is evidence the CPS will prosecute them and they will face imprisonment as a result.”
A 500 per cent increase in reported anti-Muslim hate crimes after Abedi’s bombing, was shown by Greater Manchester Police data, with 224 reports in the following month, compared with 37 during the same period last year.
The National Police Chiefs’ Council (NPCC) said police recorded 234 hate crime incidents 48 hours after the Westminster attack, 273 following the Manchester bombing and 319 two days after the London Bridge attack.
There were 171 hate crimes per day in 2016, on average.