How Our EV Charging Data Is Built
Where each figure in our open data and on our corridor pages comes from, how often it is refreshed, and what it can and cannot tell you.
Quick answer ·
How is ChargingNear.me's EV charging data built?
Station facts come from the U.S. Department of Energy’s Alternative Fuels Data Center (AFDC), synced every day at 14:00 UTC; Open Charge Map and OpenStreetMap add IDs, power and amenities weekly, and drivers add outage and correction reports. Stations from other sources fold into the AFDC station when they are within 30 meters on the same network or share a station ID. Gaps are measured along FHWA’s highway lines between DC fast chargers within 1 mile of the road, and a station is NEVI-grade with four CCS ports of 150 kW within 1 mile of a designated corridor. Every file is rebuilt daily at 07:30 UTC.
Method last changed . Run times below are live.
Where does the data come from?
Most station facts come from the Alternative Fuels Data Center Station Locator, run for the U.S. Department of Energy by the National Laboratory of the Rockies (formerly NREL). Open Charge Map and OpenStreetMap add IDs, power, amenities and hours, and a few locations AFDC does not list. Drivers add check-ins, outage reports and corrections on ChargingNear.me, and our team adds field checks. Every other figure comes from the named, dated source it cites:
- U.S. Department of Energy, Alternative Fuels Data Center Station Locator (National Laboratory of the Rockies, formerly NREL), read daily by our sync
- FHWA Highway Performance Monitoring System (HPMS), 2024 data year, public geospatial release (USDOT/BTS)
- FHWA National Highway System (USDOT/BTS National Transportation Atlas Database, updated August 8, 2025) (August 8, 2025)
- FHWA Alternative Fuel Corridors, Round 8 (USDOT/BTS National Transportation Atlas Database, Jan 16, 2025)
- U.S. Census Bureau, TIGERweb state boundaries
- Natural Earth, 1:10m admin-0 boundary lines (public domain), for the Canada and Mexico borders
- FHWA, The National Electric Vehicle Infrastructure (NEVI) Formula Program Guidance (copy hosted by AASHTO): a corridor is “fully built out” when “EV charging infrastructure is installed every 50 miles along the State’s portions of the Interstate Highway System within 1 travel mile of the Interstate” (February 10, 2022)
- FHWA, NEVI Formula Program Interim Final Guidance (supersedes the 2022–2024 guidance and leaves station spacing to states) (August 11, 2025)
- CDOT and Colorado Energy Office, 2025 Update of the NEVI Deployment Plan for Colorado (“the 50-mile target established by CDOT and CEO for this program”) (2025)
- 23 CFR part 680, National Electric Vehicle Infrastructure Standards and Requirements
- 23 CFR 680.106(b)(1), (c) and (d)(1): at least four CCS ports, each able to deliver 150 kW at once (February 28, 2023 (88 FR 12752))
- U.S. Census Bureau, Vintage 2025 Population Estimates, counties (July 1, 2025) (January 2026)
- U.S. Census Bureau, TIGERweb county boundaries (State_County layer)
- U.S. Census Bureau, Vintage 2025 Population Estimates (July 1, 2025) (January 2026)
- U.S. DOE Alternative Fuels Data Center, Vehicle Registration Counts by State (2025) (retrieved 2026-10-30)
- Colorado Department of Transportation, Highways (CDOT open data)
- Open Charge Map (openchargemap.org), user-contributed data under CC BY 4.0, for the few locations AFDC does not list
- U.S. Geological Survey, 3D Elevation Program (3DEP), ground elevation under the road on the Colorado corridor pages
- OpenStreetMap contributors, exit numbers and mountain pass names on the Colorado corridor pages (ODbL)
- Colorado Energy Office, DCFC Plazas Summary of Awards, the planned NEVI sites on the Colorado corridor pages
How often is the data refreshed?
Times are UTC. Driver reports and check-ins arrive all day and reach the files at the next daily build. A file’s version goes up only when its rows change.
| Job | Schedule | What it refreshes | Last successful run |
|---|---|---|---|
| Nationwide NREL station refresh | Daily 14:00 UTC | Every AFDC station in the 50 states and DC: new, changed and closed stations, ports, plugs and power. | |
| Gone-station check | Tuesdays 06:00 UTC | Flags stations that have been missing from AFDC for 60 days or more. | |
| Open Charge Map | Saturdays 12:00 UTC | Open Charge Map IDs and charger power, for every state. | |
| OpenStreetMap | Saturdays 13:00 UTC | OpenStreetMap IDs, amenities and opening hours. | |
| Open data files (/data) | Daily 07:30 UTC | Rebuilds every file on the open data page, with its row count, version, change date and changelog. |
How are duplicate stations handled?
Across sources. After each AFDC refresh, before counts and pages are built, a station we know from another source (such as Open Charge Map or our Google Maps scan) is folded into the AFDC station for the same place when both are open, they are within 30 meters, and they are on the same network or carry the same station ID. Two AFDC stations are never merged with each other: AFDC lists separate pedestals at one address on purpose. Stations claimed by their owners are never folded in, and every merge is recorded and can be undone.
Into locations. Stations at one place are then grouped into one location, with one page: first those at the same street address with a house number, within 150 meters and without conflicting ZIP codes, across networks and sources; then any two groups within 40 meters on compatible networks (the same, or either one non-networked) whose house numbers don’t conflict. The best row, AFDC first, gives the location its name and address.
The Public charging stations (NREL fields) file has one row per AFDC station. The corridor pages and files count locations, adding up each location’s DC fast ports.
How is the Working-Now Score calculated?
The Working-Now Score (0–100) starts at 70 for a station listed as open. It adds 10 when the listing was confirmed in the last 30 days (5 within 90 days) and subtracts 10 when the last confirmation is over a year old. Driver reports from the last 30 days move it up to +20 or down to −40, with failures weighing 1.5 times successes. A failure in the last 48 hours caps it at 40; a success in that window lifts it to at least 85.
Confirmation dates come from AFDC’s date_last_confirmed and our own verification passes. Driver reports are check-ins and one-tap answers sent on ChargingNear.me, including field checks by our team.
Exactly: a station not listed as open scores 0. A listing never confirmed counts as more than a year old. The reports move the score by 20 × (worked − 1.5 × failed) ÷ (worked + failed + 1), held between −40 and +20, and the result is rounded and kept between 0 and 100.
In the reliability roll-up file, a network, county or corridor is published only when its stations have at least 10 reports in the last 30 days. Drivers see the score on station and corridor pages; how drivers use it.
How are chargers matched to highways and corridors?
Colorado corridor pages and files (all corridors). Each corridor follows CDOT’s highway lines between two named points, by CDOT route ID. We keep every public DC fast charging location within 2 miles of the line in a straight line, and up to half a mile past either end, so the end interchange keeps its own chargers. Only locations with their own page are listed. Distances run along the highway between the points where each location is closest to it, and gaps count every DC fast charger, Tesla Superchargers included. Mile points are CDOT’s; where a corridor runs on another highway, chargers there show that highway’s mile points. Exit numbers are the nearest numbered exit in OpenStreetMap and are approximate. Elevations are the USGS 3D Elevation Program’s ground elevation under the line, every mile. The pages read live data; their files are rebuilt daily from the same rows.
U.S. highway files. Highway lines and mile markers come from FHWA’s Highway Performance Monitoring System (HPMS, 2024 data year): every mainline section a state signed as Interstate or U.S. highway. Several states leave that signing blank in HPMS (Texas, California, Maryland and Delaware among them), so a section’s signing also comes from FHWA’s National Highway System dataset, which records the posted route for the same HPMS route IDs. Sections of one highway in one state are joined end to end; a second carriageway or couplet drawn beside the first is dropped. Roads FHWA designates that are not Interstate or U.S. highways (state routes, parkways, turnpikes) use FHWA’s own corridor lines. Mile markers come from the route measure each state reports to FHWA in HPMS, where it runs continuously along the line (state_route_measure). It often matches the posted mileposts (it does for I-70 in Colorado) but not always: some states measure from a different starting point or by section. Where the measure does not run continuously, such as one that restarts by county, the markers are miles from the south or west end of the line within the state (from_south_or_west_end).
Alternative Fuel Corridors. Corridor designation comes from FHWA’s Alternative Fuel Corridors map (Round 8), matched to the highway lines within 0.1 mile. A corridor named for another road counts only where that road has no line of its own there. Source: FHWA Alternative Fuel Corridors, Round 8.
How does the NEVI test work?
Stations (the station check).
Every station in the 50 states and DC that AFDC lists as open and public with at least one DC fast port is tested against three NEVI minimums. Two are in 23 CFR 680.106 (FHWA final rule, February 28, 2023) for stations along designated Alternative Fuel Corridors: at least four ports with a CCS connector (680.106(b)(1) and (c)), each able to deliver at least 150 kW (680.106(d)(1)). The third, a location within 1 mile of a designated corridor, is the “within 1 travel mile” distance in FHWA’s February 10, 2022 NEVI guidance; part 680 itself sets no distance.
Ports and power come from AFDC’s port-by-port listing. A port counts as CCS when it has a J1772COMBO connector, including Tesla ports with a CCS adapter that AFDC lists that way. A port counts at 150 kW when AFDC lists its CCS connector at 150 kW or more; a port with no listed power does not count.
Corridor distance is the straight line from the station to the nearest designated corridor stretch (ready or pending) on the highway lines described for the gap file.
Spacing (the corridor-miles file).
Each designated highway is split at its NEVI-grade stations (those that pass the station check in this section). A stretch between two NEVI-grade stations meets the spacing when it is 50 miles or less. A stretch from a NEVI-grade station to a state line, a border or the end of the highway meets it when it is 25 miles or less, so a station within 25 more miles past that point would keep the 50. A highway with no NEVI-grade station on it does not meet it.
The 50-mile figure comes from FHWA’s February 10, 2022 NEVI guidance (“every 50 miles” along a state’s Interstates for a fully built-out corridor). FHWA’s August 11, 2025 interim final guidance superseded that and leaves spacing to states; Colorado’s plan (CDOT and the Colorado Energy Office, 2025 update) keeps a 50-mile target. 23 CFR part 680 does not set a spacing. Other states’ own targets may differ.
The Colorado corridor pages cut the same stretches to each corridor’s CDOT mile points and total designated miles only.
How are highway charging gaps computed?
Chargers are AFDC stations listed as open and public with at least one DC fast port, any network and any plug, including Tesla. A charger serves a highway when it is within 1 mile of it in a straight line. Chargers just across a state line count.
We walk each highway from end to end and record every stretch longer than 50 miles between consecutive chargers, or between a charger and a state line, the Canada or Mexico border, or the end of the highway. Gap length is measured along the highway.
The result is the highway gap file.
What are the known limits?
Highway gaps
- Straight-line distance to the highway, not driving distance to the exit.
- Where two highways share the road, the line is drawn once, under one of them, so the shared miles appear once.
- Chargers in Canada and Mexico are not in AFDC’s U.S. listing, so a gap ending at a border may be shorter in practice.
- A charger listed as open in AFDC may be down on a given day; the gaps assume it works.
NEVI station check
- AFDC lists each plug’s top power, not what every port delivers while all four charge at once, so a pass here does not prove 680.106(d)(1)’s simultaneous 150 kW.
- The test does not check the other parts of 23 CFR 680, such as 24-hour access, payment methods, uptime or networking.
- “Within 1 mile” is a straight line, not travel miles from the exit.
NEVI spacing
- Stations on a crossing highway count only when they are within 1 mile of this one.
- A stretch that is partly designated counts only its designated miles.
- Rows are per state: a highway that crosses several states has one row in each.
Working-Now Score and reliability
- Station-by-station scores and their history are not in this file; they stay under the API Terms.
- Reports come from drivers who chose to send them, not from a random sample.
Station file
- Facts are as AFDC publishes them; a correction sent to us appears in the corrections layer, not here.
Driver reports
- Reports come from drivers who chose to send them, not from a random sample, so a station with no row is not proof it works.
- No personal data: no reporter names, emails, phone numbers, user IDs or IP addresses, and nothing a driver typed in their own words.
Colorado counties
- Boundaries are simplified to about 150 meters, so a station right on a county line can land in the neighboring county.
Growth
- The month a station appears in AFDC can lag the day it opened.
State rankings
- Registration counts are for 2025; station counts are today’s.
Colorado corridors
- Each location can be up to 2 miles off the highway, so allow for the drive to and from it.
- A location with several stations is one row; its ports are the sum of its stations’ DC fast ports.
- Exit numbers are approximate. Elevations are the ground under CDOT’s line, not the road surface on a bridge or in a tunnel.
- Rows whose source is Open Charge Map come from Open Charge Map contributors under CC BY 4.0; credit them as well when you reuse those rows.
Questions about our methodology
How often is the EV charging data refreshed?
Station facts from the U.S. Department of Energy’s Alternative Fuels Data Center (AFDC) are synced every day (daily 14:00 utc). Open Charge Map and OpenStreetMap are read weekly, and every downloadable file is rebuilt daily (daily 07:30 utc); a file’s version goes up only when its rows change.
How are duplicate charging stations removed?
A station we know from another source, such as Open Charge Map, is folded into the AFDC station for the same place when the two are within 30 meters and share a network or a station ID. Two AFDC stations are never merged, and every merge can be undone. Stations at one address are then grouped into one location, with one page.
How is the Working-Now Score calculated?
It starts at 70 for a station listed as open, gains up to 10 for a recently confirmed listing, and moves up to +20 or down to −40 with drivers’ reports from the last 30 days, failures weighing 1.5 times successes. A failure in the last 48 hours caps it at 40; a success in that window lifts it to at least 85. The full rule is on this page.
How are highway charging gaps measured?
Along the highway, on FHWA’s HPMS lines, between consecutive open public DC fast chargers within 1 mile of the road, every network and plug included, Tesla too. A gap file row is any stretch over 50 miles, including to a state line, a border or the end of the highway.
How does the NEVI check decide if a station qualifies?
A station passes when AFDC lists at least four CCS ports at 150 kW or more and it sits within 1 mile of a designated Alternative Fuel Corridor. The port and power minimums are in 23 CFR 680.106; the 1 mile is from FHWA’s February 10, 2022 guidance.
Why does the data use 50 miles between NEVI stations?
FHWA’s February 10, 2022 guidance counted a corridor as built out with chargers every 50 miles. Its August 11, 2025 guidance leaves spacing to each state, and Colorado’s NEVI plan keeps 50 miles; we use 50 everywhere so states can be compared.
What are the main limits of this data?
Distances to the highway are straight lines, not driving distance; a station listed as open may be down on a given day; AFDC lists each plug’s top power, not what four ports deliver at once; and driver reports come from drivers who chose to send them. Every known limit, file by file, is on this page.
Who can answer a question about a figure?
Write to reserve@winsparking.com. Agencies: our page for agencies covers citation, the API, weekly files and corrections.