Hey its my first post and Iv been riding fixed for a while but only going short distances. The longest Ive gone was like 30 miles, and I felt like my gear was very high. I have to pedal way too much for how fast I go. I have 42/16 right now. Im going on a 40 mile ride soon and I want a much higher gear. I dont have much money to spend on this gear so Ide like to change the sprocket. What is a good high gear for long distance?

I'd say a 14T. I ride a geared bike, but spend a great deal of time in 48/16 (3:1) and 42/14 would give you the exact same ratio. That's good for ~21mph @ 90rpm depending on your tire size.

Just so I understand.
When you say your current gear was "very high"...does that mean it was it was too hard to pedal that gear over a long distance or you felt your cadence (how fast you spun the cranks) was too high?
Just want to clarify because when people say they're "geared too high," it usually means they gear is too hard for their terrain and they need to gear lower (find a gear that's easier to spin).
I ride hills and flats and use a gear similar to yours. The trick is to learn to spin. Get more comfortable spinning the cranks at a higher cadence...it's actually better for you and you'll find it's less tiring over long distances.

If you do want to gear higher, I would only drop to a 15t or possibly 14t rear cog. A 15t will put you around 75 gear inches and a 14t will put you around an 80 gear inch. An 80 is borderline too hard for longer distances. Soon as you start pedaling against a headwind for 5+ miles, your legs will really wish you had a lower gear.

Read Sheldon's section on gearing, it should be useful..
Fixed Gear Bicycles for the Road

When I mention "gear inches," I'm referring to this type of calculation.
Your 42/16 = 70.9
42/15 = 75.6
42/14 = 81

For reference, I use a 67 for everything...flats, hilly areas, etc.. and often do 30-50 mile rides on flat paved trails. I just like spinning though (higher pedal cadence).

BTW...if you happen to live in Seattle, I would be happy to let you borrow a 15t for free.
Cogs aren't expensive either...these are good for the money.
https://www.retro-gression.com/colle...dard-track-cog

If you have a rear wheel that's fixed on both sides, you can always run a 15t on one side and a 16t on the other. That way you can flip the wheel if you want to gear up/down (or a 15t on one side and a 14t on the other side).

the best gear is whatever has you spinning at your rpm preference at your average speed

Best thing you can do is learn to spin and to keep it up...

I live in a very flat area myself and run considerably smaller gear inches than your 42/16 gives you...but I always preferred spinning, and am growing old and infirm now ;-)

My kid has the exact same gearing as yours on his own sw8 phiksie - when we 1st built it he complained about having to pedal too fast to keep up with his buds who all ride bigger gearing...but from my experience I think 70ish G/I is a great all-around gearing and convinced him to stick with it to "spin to win." Now he is faster, even with his smaller gear ratio (which is not really all that small), than they are.

BTW - for your own good you should also read THIS...

yes I understand that but im not the type of person that likes to spin alot and what im looking for is to get a lot more leverage than I have now, to go longer distances more easily.

Im going to get 14 i think