If down and jump are pressed on the same frame while standing on a pipe, Yoshi both jumps and goes down the pipe. This speeds up the time it takes Yoshi to exit the screen by skipping the animation where he climbs into the pipe.
On a few pipes in the game, this trick will cause a 1-1 Warp, like in 1-1 or 2-1. It may also cause a warp to adjacent rooms like with the second pipe in 2-1 and 2-8. Since this is not a 1-1 Warp though, it is allowed in Warpless and 100% speedruns.
There are three variations of the pipe jump:
- Down + B
- Down + B + Y
- Down + B + A
*An easy way to do it is to use one hand. With your index finger on the dpad and your pinky on B, move your whole hand to press down and jump at the same time. In Lee's tutorial, he talks about the method that he uses. You should experiment a bit to find a method that works best for you!
- Each pipe jump saves 29 frames over going down the pipe normally.
- In 4-E doing an up+jump pipe entry saves 42 frames.
- Pipes (13): 1-3, 1-4, 1-6, 2-3, 2-7, 2-8, 3-8, 4-2, 4-4, 5-7(2), 6-4, 6-7
- 2-1 adjacent warp: 89 frames or 1.48s
- 2-8 adjacent warp: 208 frames or 3.46s
- Time save w/o adjacent warps: 377 frames or 6.28s
- Total time save: 674 frames or 11.23s
- Pipes (37): 1-2, 1-3, 1-4, 1-6, 1-7, 2-1, 2-3, 2-4, 2-7(2), 2-8(2), 3-2, 3-8, 4-1, 4-2(2), 4-3, 4-4, 4-5, 4-8, 5-4, 5-5, 5-7(2), 6-4, 6-7, 6-E, 2-E, 4-E(8)
- 2-1 adjacent warp: 33 frames or 0.55s
- 2-8 adjacent warp: 61 frames or 1.01s
- 4-E: 336 frames or 5.6s
- Time save w/o 4-E or adjacent warps: 841 frames or 14.01s
- Total time save: 1271 frames or 21.18s
There are many one-way gates in Yoshi's Island that can be opened backwards. The easiest method is to do an upshot at the top of the gate with some speed. The egg clips into the gate and knocks it open, thus allowing Yoshi to go through. This is used in various places to save time in all speedrun categories.
- Tap A once quickly to throw the egg -- don't hold A for a bit and then release.
- Hold up the entire time, even after tapping A, to get the angled-upshot.
- Hold B the entire time and if you miss the first shot, let Yoshi auto-flutter and try again. It is actually easier to get the fluttering gatehack than the regular one due to a bigger window.
- Run into the gate to knock it inwards a little bit to make it easier to get the gatehack to work. This greatly increases the window of success (~9 frames vs 3 frames).
Another variation of the gatehack can be seen in 6-7 where you use a Spiked Fun Guy (or it's pot). You spit it out while pushing against the gate, re-tongue it and do it once more. The negative x-velocity of the enemy opens the gate. This works with anything that bounces off of the gate. However, this trick requires the gate to be loaded in the correct sprite slot. If the gate is in a higher numbered slot than the enemy, the gatehack will not work. You can see the sprite IDs and a consistent method demonstrated here. Also check the DLC page if you would like to experiment with it for yourself.
It is possible to travel through green Piranha Plants without getting hit by throwing an egg or spitting an enemy into them. It is a 32 frame window to do so.
It is also possible to damage boost through these Piranha Plants by facing backwards and running/fluttering into them. Some might find this more consistent than the egg throwing method, however, this method is slower.
Normally, Caged Ghosts take at least 4 egg shots to jump over, however, when they load in, they grow in size. Shooting them during the growing phase causes them to stop growing and reduce by 1 size. This can be used to save both time and eggs. There are 2 of these in 3-8 . Only one is seen in Warpless speedruns.
Another Ghost Skip is used in 6-E where you spit a Mace Guy into the horizontal Caged Ghost. Using visual cues can significantly increase consistency.
Generally, the screen scrolls depending on where Yoshi is heading.
- Holding up/down will scroll the screen vertically if the level allows for it, however, this is not possible while egg-aiming.
- Jumping as the screen is scrolling will scroll it even higher compared to just holding up.
- You can also use a jump to correct the screen position if you can get it to scroll a little bit higher. 
- A perfect jump won't allow the screen to scroll vertically. 
- An upward screen scroll can also be buffered. If Yoshi is in a part of a level where the screen cannot scroll, you can hold up and then when you move to a part of the level where the screen can scroll, it will happen automatically. This can be seen in 1-4 and 1-7 100%.
Enemies, collectibles and auto-scroll triggers only spawn when the screen is scrolled properly. This is used many times in speedruns for example the 6-5 autoscroller-skip, loading in the red coins in 1-7 to skip the beanstalk and loading in a flower in 1-2 to skip the helicopter.
The game cannot have more than 24 sprites loaded on screen at once. Loading in too many sprites will either cause the game to lag or to just not load things. Keep in mind that some sprite slots are reserved for important things and will always stay loaded such as Baby Mario and the eggs that you are carrying
In speedrunning this has both pros and cons. It can be used to not load in enemies to save time, such as the Bullet Bill Launchers in 2-7. But it can also be frustrating in 100% speedruns if you overlook that a red coin or flower didn't load in.
The 4-7 Chicken Baxter is a way to bring a chicken (Huffin Puffin) to 4-8 where it can be used against Hookbill to flip him over instantly. A good chicken fight saves 10 seconds over an optimal normal Hookbill fight. It's mainly an Any% trick but it can also be used in 100%.
Important Note: When you cancel the aiming of a chicken, there is a 1 in 3 chance that it will be dropped.
A Chicken Baxter is performed by aiming the chicken and cancelling it on the same frame as you enter a goal ring. However, a certain setup is needed to make it work due to how sprite IDs work. The sprite ID of the chicken has to be higher than the goal ring.
- Running the following LUA script in the Snes9x emulator can help to find a setup and better understand sprite IDs.
- Chicken Baxter demonstration with sprite ID overlay
- Chicken Baxter beginner tutorial
- Chicken Baxter advanced tutorial
This glitch only occurs in 4-8.
If Yoshi ground pounds Hookbill before he lands on his back on the final hit of the fight, Yoshi will "blast off" into the sky. This glitch has the potential to temporarily freeze the game for up to a minute during the keyhole cutscene or even softlock the game . However, this can be avoided by always doing the final ground pound while on the left side of Hookbill, with Baby Mario and away from the right side of the stage (where the screen stops scrolling).
Off Screen Red Coin Fly Guy Shot
In levels where Fly Guys with red coins fly on screen, you can shoot them before they fly in to be able to collect the coin a little bit quicker.
This can be seen in 3-2,   4-3 , 5-1  and 5-E .
Red Coin Duplication
It is possible to duplicate red coins carried by Patrolling Fly Guys. To do this you want to:
- Tongue the Fly Guy, (don't collect the red coin).
- Spit out the Fly Guy without destroying it.
- Scroll the screen to despawn it.
- Then go back to respawn the Fly Guy.
- You should now have 2 red coins, one on the ground and one being carried by the Fly Guy.
You can dupe up to 3 red coins (4 in total) but it is incredibly hard since the timing is very tight. Instead, 100% runners opt to only dupe 1 or 2 coins, depending on the level.
Red coin dupes are used in 2-2 , 2-7 , 4-5 , 4-6   , 5-1 , 5-4  and more recently, 4-1   to get 20 red coins faster. You can dupe red coins in the last screen of 2-5   and 5-1 as a backup and the 2nd to last screen of 2-7, if you missed a coin or failed to collect one from a Shy Guy. You can also dupe red coins by using the midring, though it's only doable in 4-5.