How EVLONGHAUL Plans Your Charge Stops
Last updated: July 23, 2026
When you plan a trip on EVLONGHAUL, the planner takes your route, your vehicle, and your charge settings and turns them into a list of specific charging stops. This page explains exactly how it does that — the assumptions, the math, and the data sources — and, just as important, what the planner cannot know. Every number it shows you is an estimate built from public data. Treat it that way.
Where the vehicle numbers come from
Vehicle range, efficiency, and battery data come from the EPA's fueleconomy.gov catalog — as of mid-2026, roughly 1,443 battery-electric models from 2011 onward. Where the EPA does not publish a battery size, EVLONGHAUL estimates it from the EPA range and efficiency figures and marks it with a "≈" so you know it is derived, not official. Plug types are curated by hand, because the EPA publishes no plug data at all.
The 8% buffer and how legs are budgeted
The planner never budgets against your car's full rated range. Instead:
- Usable range = EPA rated range × 0.92. That flat 8% buffer accounts for the fact that sustained highway speeds and ordinary weather usually deliver less than the EPA combined figure.
- The first leg is budgeted as your starting charge percentage minus your minimum arrival percentage, applied to that usable range. If you start at 90% and want to arrive with at least 10%, the first leg gets 80% of your usable range.
- Every later leg assumes you charge to 80% at each stop — the practical ceiling for DC fast charging, since charging slows sharply above that — so later legs are budgeted as 80% minus your arrival reserve.
The 8% buffer is deliberately simple. It is not a physics model, and it will not cover a hard winter headwind or a long mountain climb. More on that below.
How each stop gets placed
The planner tracks your energy budget mile by mile along the route. Where the budget would run out, it looks for a real station in a window from 35 miles before that point to 5 miles after it. The window skews early on purpose: charging a little sooner than strictly necessary is cheap insurance, while pushing past your budget is not.
Within that window, the planner prefers stations with 100 kW or faster hardware, and among those it picks the one farthest along your route so you cover the most ground per stop. The next leg's budget then starts from the station's actual position on the route — not the theoretical target — so small placement differences never compound into an optimistic plan.
If no station fits the window at all, the planner does not invent one. It marks a dashed "suggested charge area" instead, which is your cue to research that stretch yourself before you commit to it.
The route line you see drives through every planned stop — including any detour off the highway — and the trip's total miles, drive time, and per-leg distances come from that real charger-to-charger route. Stop selection itself still happens along the direct route's corridor; if a detour makes a leg longer than your energy budget covers, the itinerary flags that leg with a "may exceed range" warning rather than silently assuming it works.
Where the station data comes from
Stations come from the U.S. Department of Energy's Alternative Fuels Data Center, looking at stations within about 5 miles of your route. The planner filters to public, non-call-ahead stations that have your connector on DC fast hardware of known power — or J1772 equipment if you have chosen a Level 2-only trip. When the AFDC lookup is unavailable, Open Charge Map serves as the fallback source.
You can narrow the search with the charger speed filter — any DC fast (50 kW+), 150 kW+, 250 kW+, or Level 2 only — and by connector: CCS, NACS, CHAdeMO, or J1772. If those terms are unfamiliar, start with our guide to charging levels and what the kW numbers mean.
How charge times are estimated
The charge-time figure at each stop is the time to add roughly 60% of your battery pack at an average rate of 70% of the station's rated power, capped at a 90 kW average. Why so conservative? Fast chargers taper: the peak number on the sign is reached briefly, if at all, and the average over a whole session sits well below it. A "350 kW" station will not average anywhere near 350 kW across a real charge. The estimate is built to be roughly right for a typical session rather than impressively wrong.
Your actual session will still vary with battery temperature, your state of charge on arrival, and how the station shares power — none of which the planner can see.
Routes, networks, and pin colors
The planner compares up to three alternate driving routes. If you select a preferred charging network, it favors the route that keeps the most stops on that network — sometimes a slightly longer drive is worth a more consistent charging experience.
On the map, each charge-stop pin shows its stop number and is color-coded by the station's rated charging speed:
- Green — 250 kW and up, the fastest hardware on the route.
- Orange — 100 to 249 kW, the workhorse fast-charging tier.
- Dark — under 100 kW, Level 2, or unlisted power; plan for a longer stop.
- Dashed "?" — no charger found; a suggested charge area you must plan yourself.
How far each station sits off your route shows up two ways: as text on its itinerary entry, and in the shape of the route line itself, which detours to the charger and back.
What the planner does not know
Honesty matters more than polish here, so plainly:
- No live charger status. The planner has no real-time availability, occupancy, or outage data. A station can be full, offline, or behind a locked gate, and the plan will not reflect it. Check the charging network's own app before you rely on any single stop.
- No weather model. Cold, heat, wind, and rain all cut range, and winter can cost you far more than the 8% buffer covers. See how winter affects EV range before a cold-season trip.
- No elevation model. A long climb burns range faster than flat ground; the planner treats every mile the same.
- No driving-style model. Speed, load, roof boxes, and towing all change consumption, and the planner assumes none of them.
None of this makes the plan useless — it makes it a starting point. Leave yourself margin, confirm your stops the day you drive, and carry a backup option for any leg that depends on a single station. Our EV road trip checklist walks through exactly what to verify before you leave.