While pausing the game during a meeting with the titular characters of Battletoads in the Xbox One version of the game, the pause menu theme from Battletoads will play.

According to Sean Velasco and David D'Angelo, as of November 2019, the Nintendo Switch port of Shovel Knight accounts for 25% of sales of the game, despite being released several years later.

The Shovel Knight amiibo figure, which is compatible with the Wii U and 3DS versions of the game, is the first amiibo to be able to function whilst still in its packaging, unaltered. This is because it doesn't include the blocking strip which can be found in every other amiibo packaging. Yacht Club Games made this intentional after receiving feedback from fans who wanted to keep it as a collector's item.

The figure is also the first amiibo to be produced not by Nintendo's own manufacturers. The game itself was also the first non-Nintendo developed title to receive its own amiibo.

The feat called "only you", which requires the player to dig up campfire ashes, is a reference to Smokey the Bear and his catchphrase "only you can prevent wildfires"

Vitas Varnas, actor, occasional Game Grumps contributor and writer for VGFacts and Did You Know Gaming?, appears as a portrait in the Hall of Champions. People who had pledged $200 or more to the game's Kickstarter would have a portrait of them appear in-game.

Matt, from the let's play series TwoBestFriends, appears as a portrait in the Hall of Champions. Anyone who had pledged $200 or more to the game's Kickstarter had a portrait of them put up.

The traveler bosses that Shovel Knight encounters were created by backers who had donated $1,000 or more to the game's Kickstarter. The traveler bosses were created by the following pledgers:
• Reize by Danny D. Henderson
• Mr. Hat by Alexander Hatzikides
• Baz by Matt and Woolie
• Phantom Striker by Steven Ness

The enemy Liquid Samurai was created by Max VanDuyne.

The wandering boss Baz was based on an unused character design from Street Fighter II referred to as 'Zubaz'. Baz was created by Matt and Woolie of the let's play series TwoBestFriends as a backer reward for pledging to the game's Kickstarter. Baz has appeared in multiple games which Matt and Woolie have put him in as a Kickstarter pledge incentive.

All the music for the game was composed on Famitracker, a program which creates music for the NES. This means that the music can be played back on an actual NES, and the composer, Jake "Virt" Kaufman, has released the .nsf file that can be played back on a real NES using a flash cartridge.

Shovel Knight has over 300 cheat codes. These can be activated by inputting a certain combination of letters into the name selection screen when starting a new game.

After defeating all of the Order of No Quarter in the Tower of Fate: Ascent level, if you save the Knights and then talk to King Knight whilst wearing the Ornate Plate armor, he will compliment Shovel Knight for assumingly copying his style.

If an investor pledged $200 or more on the Kickstarter page for Shovel Knight, your face would be included in the level 'Hall of Champions'. One of these donators was Arin 'egoraptor' Hanson, animator and co-host of Game Grumps. Because Arin forgot to send his face to the development team, they instead used his appearance from Game Grumps.

If you enter " WSWWAEAW" at the name entering screen, it will activate a cheat that will turn most of the words shovel, knight, health, mana, and fate into the word 'Butt'.