The 124-mile Kings Canyon High Basin Route can be completed as a point-to-point thru-hike, or as a closed loop with the addition of 25 trail miles. Alternatively, shorter segments of the KCHBR can be completed as section-hikes.
The number of miles you should expect to cover each day is primarily a function of your fitness and the amount of off-trail travel on your particular route. If you are considering the KCHBR, presumably you know about how many miles you like to hike each day when on-trail. The off-trail miles will be slower, perhaps much slower. If you are an excellent navigator and are comfortable when scrambling or hiking on uneven surfaces, expect to slow by 25 percent plus/minus. At the other end of the spectrum, I have seen veteran backpackers maintain just 25 percent of their normal on-trail walking speed when off-trail. Not sure how you will fare? Start conservatively with an itinerary that should be well within your ability and time allowance.
A complete thru-hike of the Kings Canyon High Basin Route between Lodgepole and Road’s End is 124 miles. To simplify your travel logistics, budget enough time and food to hike an additional 25 miles on trail in order to make a full loop.
The KCHBR can also be section-hiked. In the Kings Canyon High Basin Route Guide, there are nine specific itineraries, ranging from 30 to 80 miles. The section-hiking opportunities are hardly exhausted by these prescribed routes, however — given the number of trailheads, trails, and off-trail routes in Sequoia-Kings, the options seem nearly infinite. Rather than go down that rabbit hole, I stopped at nine since the entire route was covered and since there was a good range of mileages.