Good starting recipe, for Serranos also; I never seed or devein peppers, but do slice or cut in strips. Thin-sliced onion and carrot are nice added to this. Stuff an empty jar with peppers, fill with water, pour off to a measure. You now know about how much (preferably apple)vinegar needed. Cut sugar by half or more; peppers do not want to be sweet.
The drier the weather, the hotter the pepper; I live between the Hatch and Mesilla Valleys in New Mexico, and personally consume over 100 lbs of chile annually.

My jalepenos brand new or old on vine have all been very HOT!. I am going to jar without a hot bath as this leaves them too mushy even tho I use alum also

Nice texture/ flavor....forgot the icewater bath but they turned out nice any old how. Mixed in banana peppers and garlic.

This recipe is a keeper. I too sliced the japs, left the seeds and added garlic powder and onion powder. I used 1/2 apple cider, 1/2 white vinegar and just eyeballed the amounts of all the ingredients. Extremely easy and delicious. I was concerned about the sugar but they don't come out super sweet - more like a touch of sweet. Now I know what to do with my bumper crop of japs all through the summer.

Like the previous comments, I, too slice them in rings, seeds in. Just a touch of onion and garlic powder, too. They are PERRRFECT every time. (Curious to see how the MO drought will affect the "hotness" of this year's crop. Even with tons and tons of watering, the peppers are very small and came on much later this year.)

5 cups vinegar and 5 cups sugar were more than enough for 7 pints. I followed the previous suggestion, leaving seeds in and adding 1 tablespoon garlic power and 1 tablespoon onion powder to the liquid. I also used a mixture of apple cider vinegar and white vinegar. Delish!

Excellent recipe and extremely easy! I made 2 changes, I sliced the peppers, leaving the seeds in, and added a touch of onion and garlic powders. WOW! Very tasty.