If Hitler had waited to perfect jet technology, etc before starting WWII how would that have changed things?

It is impossible to tell. There are so many potential game changers. He might have had carriers filled with jets and controlled the sea. However, the Allies would have stepped up their development of sub warfare. A single battle can change the results.
Basically it came down to how quickly and much blood and treasure are the two sides willing to throw in the meat grinder. The side with the most access to manpower, food, and fuel would win.

Hitler’s biggest mistake was invading the Soviet Union and the resulting destruction of most of his forces in the resulting pwnage. At some point, superior technology is trumped by sheer numbers.
The war may had been longer, but would still have lost.
The difference I can see is all of Europe ending up under Soviet rule.

Hitler survived in office due to his hate mongering. Blame the Jews, blame the infirm, blame the filthy and impure. He could not have stayed Chancellor/President/Leader of Germany without it, and it required the invasions of Poland, France, etc.

There’s no way to know. The American technology effort during WWII was phenomenal. The appearance of the jet engine might have prompted speeded up invention on our side of the pond.

You have a lot of question which create a lot of if’s. Superior technology does not automatically create a win. Hitler expanded his territory too quickly. He did not have the areas he had already conquered under control before he pressed onto his next target. The blitzkrieg worked to his advantage initially because the invaded countries were not prepared to repel an invasion; however, had he gotten them under control prior to advancing further, he may have stayed in power. Another mistake was to become allies with Japan and instigate the attack on Pearl Harbor. America was tending toward a isolationist policy prior to the attack. America may have entered the war at a later period even without the attack; however, it was definitely a game changer at that time.

Even if Germany had the jet prior to anyone else, it would not have stayed that way for long. Enough people were dissatisfied with him the technology would have been leaked. The bomb is a different story altogether. Having the atomic bomb and using it would have made a significant difference, as it did when America used it. Hitler would have never shared power with Japan as he considered them sub-human as well. Maybe an uneasy truce at first, but ultimately ending up with trying to take over the entire world.

Tried to answer as best I could, but so many variables to account for.

No way to tell. The British actually had a working jet engine before the Germans did. Germany just developed theirs faster than the British.

Japan would have attacked Pearl Harbor even without the alliance with Germany. Germanies big mistake was declaring war on the USA. There was enough opposition to going to war in Europe that the US might have stayed out of the war with Germany and Italy if they had not declared war.

Hitler was a chronic macro manager who screwed up a lot of efforts of his military commanders. He was paranoid trusting few to do right. That was his undoing. He also kept one of his best armies bottled up in Finland pretty much the entire war to keep out the Russians. He spent too much treasure at Pinemunde searching for super weapons when if he stayed focused on the tried and true conventional weaponry would have served him better. It was one miscalculation after another that cost him. That and the fielding of the U.S. P-51 fighter plane that raised the bar on fighter aircraft in spite of jet technology.

Hitler did have a few jet planes. in their infancy, they had many flaws and most were shot down. i don’t think waiting for jet technology to advance was an option for Hitler. He did what he did with what he had, at the time. Hitler was definetely on the right track with the jet engine, but the advancing forces did not allow him the time and thank God for that.

there was a big get to be had by both the Russian and US govts to get hold of these scientists of Hitler to advance their own knowledge of rockets and jet propulsion. They, it turned out were really on to something big. And the rest is history.

The momentum of Hitler’s rise to power meant he had to go to war when he did. He had led Germany to expect great things that four years of peace were not going to provide. I don’t think waiting four years would have helped his chances of winning the war anyway.

What Hitler’s biggest blunder attacking the Soviets near winter when his resources were thin, bringing the US into the fray, not letting his genreals do their job, attacking to fast and grabing land he could not support properly with supplies, or not waiting until his super weapons were bug free and could work as well as an AK-47? Or maybe his biggest blunder not mining the US coast or firinf torpedoes at the docks to disrupt supplies leaving for Europe?

I think he really screwed the pooch when he invaded Russia. Nobody can do that and win.

Eventually he would still have lost. Perhaps German resistance would have succeeded in 1947. Totalitarian regimes are bound to fail at some point. Besides there are always spies and jet technology can be copied.