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new news: [September 10th, 2022]

I need to do some server upgrades, hence pctplanner will be offline at 1:30pm Saturday September 10th PDT. It shouldn't take long
Data Changes
PCT Data Differences
From 1997-May 2012, this program utilized trail data from the 1995 edition of the California PCT Guidebook and the 1990 edition of the Oregon/Washington PCT guidebook.

This planning program now uses data from the 2005 edition of the PCT Data Book. The Data Book derives its data points from the 2003 edition of the California PCT Guidebook and the 2000 edition of the Oregon/Washington PCT guidebook. Below are comparisons between the older and the newer data. See note below about the 2004 Oregon/Washington guidebook.

Important: Existing hiking plans are now using the updated data. The distance differences are not significant and at most (in one instance) would add another 2-3 hours hiking time for an entire trail section.

Furthermore, there is alternate (and more up to date) trail distance data available via Halfmile's Trail Notes. In the Spring of 2012 I set out to use Halfmile's Trail data for the program as it is more up to date and accurate (especially concerning detours/etc). I was unable to use this data due to the trail elevation points being GPS-derived. GPS elevations tend to be a little bit off when the trail goes up or down steeply. This caused the PCT to have an excessive amount of elevation gain that threw off the planner calculations too much. I would still strongly recommend the use of his trail notes so you can make manual adjustments to your plan as needed.

What is on pctplanner.com right now is "accurate enough" so I haven't revisited the issue. From feedback I have heard over the years, people's hiking plans have not been off due to elevation and distance data not matching reality.

2/24/2014 update:
If you really want to know how complicated getting accurate elevation gain/loss information for the PCT is, I suggest reading this very lengthy posting on Halfmile's blog.

From: David Lippke <lippke.list at gmail>
Date: Mon, Feb 24, 2014 at 3:07 PM
Subject: [pct-l] PCT gain/loss; notes from the actual Halfmile source
To: PCT <pct-l@backcountry.net>

Hi, Lon alerted me regarding the PCT elevation gain/loss stats conversation
here and so I thought some direct information might help. I'm the author
and maintainer of the Halfmile apps and I generated all the elevation data
and gain/loss numbers published for the last three annual cycles. I spend
most of my time working on improving both the horizontal and vertical
accuracy of all our PCT data. This effort has ballooned over the last
couple years involving more than just myself and Halfmile with the
deployment of survey grade equipment to the trail, custom GPS logging
devices, and now further generations of all that we are scrambling to
deploy for the 2014 season.

Anyway, people often wonder how we calculate elevation gain and loss
numbers along the PCT. It turns out that this is a surprisingly complex
and technical process. The net is that we currently generate profiles
that are much more accurate than, say, the ones that Google Earth
produces. That said, there is still substantial room for improvement and
we are working on that.

The technical TLDR is that our point elevation values are produced by
heavily processing USGS DEM 1/3 arc second data. Our gain / loss
calculations then operate over this set using a smoothing factor consistent
with the average error present in the DEM data and the average horizontal
"side to side" path jitter observed along side slopes.

Most will want to stop reading here. 100% tech talk follows. You have
been warned. :)

Going on in more detail, the process does not involve using GPS elevation
data at all. As noted by Brick, elevation values obtained from GPS units
are much too noisy for use in gain and loss calculations -- even from the
survey grade equipment that we now use. Instead, our raw source for
elevation data is the USGS 1/3 arc second DEM (Digital Elevation Model)
which provides average elevation values over rectangles that are
approximately 8x10 meters on a side (the "8" varies with latitude).

We start with our best filtered GPS horizontal data for each bit of
trail. This ranges in horizontal accuracy from 1/2 meter (California
sections L through O) to 3-5 meter accuracy (e.g., WA J) to unknown
accuracy data that we hand select from the competing data sets. Over 2014
for the 2015 update, we hope to bring the average horizontal accuracy for
the entire PCT to the vicinity of a single meter.

Then we translate all those horizontal points to the horizontal datum used
by the USGS and we fetch the DEM elevation values needed generate a grid of
525 points surrounding each subject point. Using those 525 points, we
generate a two dimensional spline interpolation and query it at the exact
point. This process is repeated for all 3/4 million horizontal data
points and involves almost 11 million unique 1/3 arc second DEM values.

So at this point in the process we have the best possible estimate for the
elevation of each track point and way point expressed in terms of the
NAVD88 vertical datum (quasi MSL) with the primary error sources being that
of the USGS DEM (RMSE ~2.5 meters) and that of our collected horizontal

In the next step, we reduce the horizontal point count so that all sections
stay within Garmin's 10K track point limit. We do this by applying the
Ramer-Douglas-Peucker algorithm with a 1.9 meter sigma overall and, in more
accurate sections, a 1.25 meter sigma. In other words, when the trail is
going along a straight road or the aquaduct, the points can be several
hundred meters apart but in tight turns they may only be a couple meters

Finally, to calculate gains and losses between points, a tally is kept from
track point to track point except that no gain or loss is recorded until a
track point is reached that has an elevation loss or gain more than 5
meters from the starting track point. When that occurs, the algorithm
moves forward to the current end track point and picks up the counting
again. When reporting the gain / loss to a particular way point, any
residual in the smoothing is closed out so that the numbers all "add
up". As a side note, this creates a small numerical issue when one
decides to total our published per-section numbers over the whole trail and
compare those to the whole trail numbers in the (soon to be released) 2014
version of the Halfmile apps -- our per-section numbers are "closed out"
with respect to this 5 meter smoothing but the app just keeps rolling
through the boundaries.

Sorry for the tech talk, but I just wanted to address all the speculation
about what feeds into these calculations. Questions are always welcome
and so is project involvement -- we have all manner of "task" available for
the inclined. :)

All the best,
David Lippke aka White Jeep

p.s. to contact me directly, please write directly to
lippke@gmail.comversus the .list address you see here.
Alternatively, you can find me on
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Reproduction is prohibited without express permission.

Since I had the distance data available however, I included a table below of the section differences between the data this planner currently uses and Halfmile's PCT data (3/26/2012 revision).

I did attempt to update the distance/elevation data to that of 2004 edition of the OR/WA PCT guidebook, but did not include any distance changes for several reasons. The biggest reason I didn't include the changes was because the summary data for each section in the 2004 OR/WA guidebook didn't always match the data point values when added up. I couldn't be sure if these were typos or not, so I chose to just not make any changes. If a discrepancy did exist, it was less than a mile for a total trail section. The only exception was Section A of Oregon (Seiad Valley to I-5). This section is 2.4 miles longer (than what this planner states) if you go by the 1990 and 2004 OR/WA guidebooks.

Current Program Data vs Old Program Data
(2003/2000 guidebooks vs 1995/1990 guidebooks)

US/Mexico Border to Mt. Laguna
2003 CA / 2000 ORWA Guidebooks:42.3mi5570ft
1995 CA / 1990 ORWA Guidebooks:42.2mi5475ft

Mt. Laguna to Idyllwild
2003 CA / 2000 ORWA Guidebooks:136.3mi13778ft
1995 CA / 1990 ORWA Guidebooks:138.0mi13721ft

Idyllwild to Wrightwood
2003 CA / 2000 ORWA Guidebooks:185.0mi20397ft
1995 CA / 1990 ORWA Guidebooks:184.1mi20397ft

Wrightwood to Acton
2003 CA / 2000 ORWA Guidebooks:80.6mi9233ft
1995 CA / 1990 ORWA Guidebooks:79.3mi9013ft

Acton to Agua Dulce
2003 CA / 2000 ORWA Guidebooks:10.2mi1382ft
1995 CA / 1990 ORWA Guidebooks:9.2mi1240ft

Agua Dulce to Highway 58 (California)
2003 CA / 2000 ORWA Guidebooks:112.2mi12128ft
1995 CA / 1990 ORWA Guidebooks:108.8mi12128ft

Highway 58 (California) to Kennedy Meadows Store
2003 CA / 2000 ORWA Guidebooks:136.2mi15310ft
1995 CA / 1990 ORWA Guidebooks:131.4mi15310ft

Kennedy Meadows Store to Lone Pine
2003 CA / 2000 ORWA Guidebooks:42.0mi7512ft
1995 CA / 1990 ORWA Guidebooks:42.0mi7512ft

Lone Pine to Independence
2003 CA / 2000 ORWA Guidebooks:45.4mi6775ft
1995 CA / 1990 ORWA Guidebooks:45.4mi6775ft

Independence to Muir Trail Ranch
2003 CA / 2000 ORWA Guidebooks:66.0mi10941ft
1995 CA / 1990 ORWA Guidebooks:66.0mi10891ft

Muir Trail Ranch to Vermillion Valley Resort
2003 CA / 2000 ORWA Guidebooks:21.0mi3950ft
1995 CA / 1990 ORWA Guidebooks:20.9mi3950ft

Vermillion Valley Resort to Reds Meadow
2003 CA / 2000 ORWA Guidebooks:29.4mi4484ft
1995 CA / 1990 ORWA Guidebooks:29.4mi4484ft

Reds Meadow to Highway 108 (Sonora Pass)
2003 CA / 2000 ORWA Guidebooks:111.7mi16876ft
1995 CA / 1990 ORWA Guidebooks:111.7mi16876ft

Highway 108 (Sonora Pass) to Echo Lake Resort
2003 CA / 2000 ORWA Guidebooks:76.2mi7655ft
1995 CA / 1990 ORWA Guidebooks:76.2mi7635ft

Echo Lake Resort to Belden
2003 CA / 2000 ORWA Guidebooks:194.7mi21782ft
1995 CA / 1990 ORWA Guidebooks:193.7mi21482ft

Belden to Old Station
2003 CA / 2000 ORWA Guidebooks:88.5mi10330ft
1995 CA / 1990 ORWA Guidebooks:88.5mi10275ft

Old Station to Burney Falls SP
2003 CA / 2000 ORWA Guidebooks:45.9mi1457ft
1995 CA / 1990 ORWA Guidebooks:45.9mi1457ft

Burney Falls SP to Etna
2003 CA / 2000 ORWA Guidebooks:182.7mi19144ft
1995 CA / 1990 ORWA Guidebooks:182.7mi19144ft

Etna to Seiad Valley
2003 CA / 2000 ORWA Guidebooks:55.8mi4165ft
1995 CA / 1990 ORWA Guidebooks:55.8mi4165ft

Seiad Valley to Hyatt Lake Resort
2003 CA / 2000 ORWA Guidebooks:88.1mi12651ft
1995 CA / 1990 ORWA Guidebooks:88.1mi12651ft

Hyatt Lake Resort to Shelter Cove Resort
2003 CA / 2000 ORWA Guidebooks:162.0mi13767ft
1995 CA / 1990 ORWA Guidebooks:158.7mi13610ft

Shelter Cove Resort to Elk Lake Resort
2003 CA / 2000 ORWA Guidebooks:46.1mi3501ft
1995 CA / 1990 ORWA Guidebooks:45.5mi3501ft

Elk Lake Resort to Big Lake Youth Camp
2003 CA / 2000 ORWA Guidebooks:42.6mi3660ft
1995 CA / 1990 ORWA Guidebooks:42.4mi4650ft

Big Lake Youth Camp to Olallie Lake
2003 CA / 2000 ORWA Guidebooks:52.2mi6170ft
1995 CA / 1990 ORWA Guidebooks:52.2mi6170ft

Olallie Lake to Timberline Lodge
2003 CA / 2000 ORWA Guidebooks:54.2mi4885ft
1995 CA / 1990 ORWA Guidebooks:54.2mi4885ft

Timberline Lodge to Stehekin
2003 CA / 2000 ORWA Guidebooks:466.8mi64457ft
1995 CA / 1990 ORWA Guidebooks:468.3mi64142ft

Stehekin to Manning Park
2003 CA / 2000 ORWA Guidebooks:89.4mi13353ft
1995 CA / 1990 ORWA Guidebooks:86.6mi12723ft

Current Program Data vs Halfmile's PCT Notes
(2003/2000 guidebooks vs Halfmile's Trail Notes)

Guidebook Trail Notes
From/To Mile Point Distance Distance Difference
US/Mexico Border to Lake Morena Campground
20.6mi 20.0mi -0.6
Lake Morena Campground to Highway 8
5.4mi 6.6mi 1.2
Highway 8 to Mt. Laguna
16.3mi 16.0mi -0.3
Mt. Laguna to Highway 78
35.3mi 34.7mi -0.6
Highway 78 to Highway 79
8.1mi 32.2mi 24.1
Highway 79 to Highway 74
41.7mi 42.4mi 0.7
Highway 74 to Idyllwild
27.3mi 27.5mi 0.2
Idyllwild to Interstate 10
31.0mi 30.1mi -0.9
Interstate 10 to Ziggy & Bear (closed)
1.5mi 1.3mi -0.2
Ziggy & Bear (closed) to Highway 18
63.0mi 55.2mi -7.8
Highway 18 to Highway 173 (south crossing)
39.0mi 48.3mi 9.3
Highway 173 (south crossing) to Highway 138 (near I-15)
15.5mi 14.7mi -0.8
Highway 138 (near I-15) to Interstate 15
13.5mi 13.0mi -0.5
Interstate 15 to Wrightwood
21.5mi 21.5mi -0
Wrightwood to Acton
80.6mi 80.7mi 0.1
Acton to Agua Dulce
10.2mi 10.3mi 0.1
Agua Dulce to Green Valley
24.2mi 23.7mi -0.5
Green Valley to Lake Hughes
7.7mi 7.5mi -0.2
Lake Hughes to Highway 138
32.1mi 31.9mi -0.2
Highway 138 to Tehachapi
39.9mi 40.9mi 1
Tehachapi to Highway 58 (California)
8.3mi 8.0mi -0.3
Highway 58 (California) to Highway 178 (Walker Pass)
85.4mi 85.5mi 0.1
Highway 178 (Walker Pass) to Kennedy Meadows Store
50.8mi 50.2mi -0.6
Kennedy Meadows Store to Lone Pine
42.0mi 43.1mi 1.1
Lone Pine to Independence
45.4mi 43.6mi -1.8
Independence to Muir Trail Ranch
25.3mi 68.8mi 43.5
Muir Trail Ranch to Vermillion Valley Resort
21.0mi 21.0mi 0
Vermillion Valley Resort to Reds Meadow
29.4mi 28.0mi -1.4
Reds Meadow to Highway 120
36.1mi 35.8mi -0.3
Highway 120 to Highway 108 (Sonora Pass)
75.6mi 76.0mi 0.4
Highway 108 (Sonora Pass) to Highway 4 (Ebbets Pass)
31.6mi 31.7mi 0.1
Highway 4 (Ebbets Pass) to Highway 50
43.1mi 42.7mi -0.4
Highway 50 to Echo Lake Resort
1.5mi 1.6mi 0.1
Echo Lake Resort to Highway 40
61.3mi 61.1mi -0.2
Highway 40 to Interstate 80
3.0mi 3.4mi 0.4
Interstate 80 to Highway 49
38.8mi 38.5mi -0.3
Highway 49 to Quincy
72.6mi 72.0mi -0.6
Quincy to Belden
19.0mi 19.9mi 0.9
Belden to Highway 70
0.1mi 0.1mi 0
Highway 70 to Highway 36
46.5mi 45.6mi -0.9
Highway 36 to Drakesbad Guest Ranch
17.5mi 18.5mi 1
Drakesbad Guest Ranch to Old Station
24.4mi 24.2mi -0.2
Old Station to Highway 44
4.1mi 3.7mi -0.4
Highway 44 to Highway 299
8.5mi 34.2mi 25.7
Highway 299 to Highway 89
6.7mi 6.8mi 0.1
Highway 89 to Burney Falls SP
1.0mi 1.0mi 0
Burney Falls SP to Interstate 5 (California)
82.9mi 83.0mi 0.1
Interstate 5 (California) to Highway 3
59.7mi 59.8mi 0.1
Highway 3 to Highway 93
19.9mi 20.1mi 0.2
Highway 93 to Etna
20.2mi 20.1mi -0.1
Etna to Seiad Valley
55.8mi 55.5mi -0.3
Seiad Valley to Callahan's Lodge
64.2mi 64.8mi 0.6
Callahan's Lodge to Interstate 5 (Oregon)
0.3mi 0.2mi -0.1
Interstate 5 (Oregon) to Highway 66
17.3mi 16.6mi -0.7
Highway 66 to Hyatt Lake Resort
6.3mi 6.2mi -0.1
Hyatt Lake Resort to Fish Lake Resort
30.2mi 30.5mi 0.3
Fish Lake Resort to Highway 140
0.2mi 0.2mi 0
Highway 140 to Highway 62
49.8mi 48.8mi -1
Highway 62 to Highway 138 (Oregon)
22.1mi 23.2mi 1.1
Highway 138 (Oregon) to Forest Road 60
30.4mi 31.5mi 1.1
Forest Road 60 to Shelter Cove Resort
29.3mi 28.7mi -0.6
Shelter Cove Resort to Highway 58 (Oregon)
1.8mi 1.3mi -0.5
Highway 58 (Oregon) to Elk Lake Resort
44.3mi 45.1mi 0.8
Elk Lake Resort to Highway 242
31.2mi 30.4mi -0.8
Highway 242 to Big Lake Youth Camp
11.4mi 11.8mi 0.4
Big Lake Youth Camp to Highway 20 (Oregon)
6.0mi 6.1mi 0.1
Highway 20 (Oregon) to Olallie Lake
46.2mi 46.2mi 0
Olallie Lake to Forest Road 57
30.3mi 29.4mi -0.9
Forest Road 57 to Forest Road 58
8.9mi 8.9mi 0
Forest Road 58 to Highway 26
5.0mi 5.0mi 0
Highway 26 to Highway 35
5.0mi 5.6mi 0.6
Highway 35 to Timberline Lodge
5.0mi 5.2mi 0.2
Timberline Lodge to Interstate 84
47.8mi 47.1mi -0.7
Interstate 84 to Wind River Road
34.0mi 33.3mi -0.7
Wind River Road to Road 23
48.8mi 49.2mi 0.4
Road 23 to Highway 12
64.9mi 65.5mi 0.6
Highway 12 to Highway 410 (Chinook Pass)
29.5mi 29.0mi -0.5
Highway 410 (Chinook Pass) to Forest Road 52 (Tacoma Pass)
40.2mi 40.9mi 0.7
Forest Road 52 (Tacoma Pass) to Interstate 90
29.3mi 29.1mi -0.2
Interstate 90 to Highway 2 / Tye Cr. Lodge
74.5mi 74.0mi -0.5
Highway 2 / Tye Cr. Lodge to Stehekin
97.8mi 104.2mi 6.4
Stehekin to Highway 20 (Rainy Pass)
19.7mi 19.1mi -0.6
Highway 20 (Rainy Pass) to Manning Park
39.2mi 69.5mi 30.3
Totals: 2,542.8mi 2,668.8mi 126.0mi

Disclaimer: all calculations and data are believed to be correct but are not guaranteed.
Please double check the calculations and trail/resupply data before starting a hike.