We have been inundated with a wealth of fantastic photos after putting out an appeal for them on Facebook.
This gallery has been updated throughout the day as more and more pictures have been sent over!
MORE: Best World Book Day photos from 2021, World Book Day excitement grips Portsmouth as children become their favourite superheroes
Unfortunately due to the overwhelming amount of photos we were sent and time constraints, we have not been able to feature every single one sent to us today – despite hoping to be able to do so.
But we tried to feature as many as possible - and there are over 50 images in our gallery!
The gallery is at the bottom of this article – and make sure to click through all the pages!
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45. Joker, Cruella Deville and Malificent
Teddy Hartnett aged 7 as ‘The Joker’, Kitty Hartnett aged 6 as ‘Cruella Deville’ and Blu-Belle Hartnett age 9 as ‘Malificent’ from Emsworth Hampshire Photo: Emma Hartnett
46. Peppa Pig
Ava, 2, from Gosport dressed as Peppa Pig for World Book Day. Photo: Chloe Strong
47. BFG
Jenson Byng, Age 5, from Portsmouth dressed as the BFG for World Book Day. Photo: Daisy Clapp
48. Dalmatian and King Kong
Vegas and Leo Edwards, Age 6 and 5, from Paulsgrove, dressed as Dalmatian and King Kong for World Book Day. Photo: Katherine Edwards