# NHTSA API: Decode a vehicle VIN

> Identifies a vehicle from its 17-character VIN using NHTSA vehicle data. Missing details are returned as null; decoding errors and warnings are included.

Unofficial. Not affiliated with or endorsed by NHTSA.

- Page: https://fous.com/methods/nhtsa.gov/decode-vin
- Method: `nhtsa.gov/decode_vin`, version 1
- Website: nhtsa.gov
- Returns: make, model, model year, trim, body style, engine, fuel and drive type, plant, warnings, decoded variables
- Effect: read (it gets data and changes nothing)
- Sign-in: none needed
- Cost: 1 credit per completed run (1¢ with pay as you go); failed runs are free
- Verified: Nov 2, 2026

## Inputs

| Field | Type | Required | In the run below | Description |
|---|---|---|---|---|
| `vin` | string | yes | `" 1hgcm82633 a004352 "` | The 17-character vehicle identification number from the dashboard, door frame, or registration. Spaces and lowercase letters are accepted. |
| `model_year` | integer | no | `2003` | Optional known model year for more precise decoding of older vehicles; 0 lets NHTSA determine it. Default 0. |

## Output

From a run on Oct 23, 2026, shortened. Its input:

```json
{
  "vin": " 1hgcm82633 a004352 ",
  "model_year": 2003
}
```

Its output:

```json
{
  "vin": "1HGCM82633A004352",
  "make": "HONDA",
  "trim": "EX-V6",
  "doors": 2,
  "model": "Accord",
  "engine": {
    "cylinders": 6,
    "horsepower": 240,
    "displacement_liters": 2.998832712
  },
  "page_url": "https://vpic.nhtsa.dot.gov/decoder/VinDecoder?VIN=1HGCM82633A004352&ModelYear=2003",
  "warnings": [],
  "fuel_type": "Gasoline",
  "body_style": "Coupe",
  "drive_type": null,
  "model_year": 2003,
  "plant_city": "MARYSVILLE",
  "manufacturer": "AMERICAN HONDA MOTOR CO., INC.",
  "transmission": "Automatic",
  "vehicle_type": "PASSENGER CAR",
  "plant_country": "UNITED STATES (USA)",
  "decoded_variables": [
    {
      "value": null,
      "value_id": null,
      "variable": "Suggested VIN",
      "variable_id": 142
    },
    {
      "value": "0",
      "value_id": "0",
      "variable": "Error Code",
      "variable_id": 143
    },
    {
      "value": null,
      "value_id": null,
      "variable": "Possible Values",
      "variable_id": 144
    }
  ]
}
```

## Run it

From code, with a Fous API key in `FOUS_API_KEY`; the answer's `data` holds the output:

```bash
curl https://api.fous.com/v1/runs \
  -H "Authorization: Bearer $FOUS_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"method":"nhtsa.gov/decode_vin","input":{"vin":" 1hgcm82633 a004352 ","model_year":2003}}'
```

From an AI agent connected to the Fous MCP server: its `run` with the same method and input. To connect one, give it `set up https://fous.com/SKILL.md`.

## Ask your agent

- What make and model is the car with VIN 1HGCM82633A004352?
- Can you decode this 17-character VIN I found on my door frame: 2T1BURHE0JC034567 and tell me the engine and body style?
- I'm buying a used truck, the VIN is 1FTFW1ET5DFC10312. What plant built it and what drive type does it have?
- Look up the trim and fuel type for VIN 5YJSA1E26JF254178 on nhtsa.gov, it's a 2018 model.
- My registration lists VIN wa1bnafy8j2014456 but the dealer says it's a different year. Can you check what model year the decoder gives and flag any warnings?

## Input schema

```json
{
  "type": "object",
  "required": [
    "vin"
  ],
  "properties": {
    "vin": {
      "type": "string",
      "examples": [
        "1HGCM82633A004352"
      ],
      "description": "The 17-character vehicle identification number from the dashboard, door frame, or registration. Spaces and lowercase letters are accepted."
    },
    "model_year": {
      "type": "integer",
      "default": 0,
      "maximum": 9999,
      "minimum": 0,
      "examples": [
        2003
      ],
      "description": "Optional known model year for more precise decoding of older vehicles; 0 lets NHTSA determine it."
    }
  },
  "additionalProperties": false
}
```

## Output schema

```json
{
  "type": "object",
  "required": [
    "vin",
    "make",
    "model",
    "model_year",
    "trim",
    "body_style",
    "vehicle_type",
    "doors",
    "engine",
    "fuel_type",
    "transmission",
    "drive_type",
    "manufacturer",
    "plant_city",
    "plant_country",
    "warnings",
    "page_url",
    "decoded_variables"
  ],
  "properties": {
    "vin": {
      "type": "string",
      "description": "The normalized 17-character VIN."
    },
    "make": {
      "type": [
        "string",
        "null"
      ],
      "description": "Vehicle make."
    },
    "trim": {
      "type": [
        "string",
        "null"
      ],
      "description": "Trim or equipment grade."
    },
    "doors": {
      "type": [
        "integer",
        "null"
      ],
      "description": "Number of doors."
    },
    "model": {
      "type": [
        "string",
        "null"
      ],
      "description": "Vehicle model."
    },
    "engine": {
      "type": "object",
      "required": [
        "cylinders",
        "displacement_liters",
        "horsepower"
      ],
      "properties": {
        "cylinders": {
          "type": [
            "integer",
            "null"
          ],
          "description": "Number of engine cylinders."
        },
        "horsepower": {
          "type": [
            "number",
            "null"
          ],
          "description": "Engine power in horsepower, when listed."
        },
        "displacement_liters": {
          "type": [
            "number",
            "null"
          ],
          "description": "Engine displacement in liters."
        }
      },
      "description": "Engine details when NHTSA reports them.",
      "additionalProperties": false
    },
    "page_url": {
      "type": "string",
      "description": "Link to this VIN's NHTSA decoder result page."
    },
    "warnings": {
      "type": "array",
      "items": {
        "type": "string"
      },
      "description": "NHTSA decoding errors or warnings in plain words; empty if none are reported."
    },
    "fuel_type": {
      "type": [
        "string",
        "null"
      ],
      "description": "Primary fuel type."
    },
    "body_style": {
      "type": [
        "string",
        "null"
      ],
      "description": "Vehicle body style."
    },
    "drive_type": {
      "type": [
        "string",
        "null"
      ],
      "description": "Drive type written in words."
    },
    "model_year": {
      "type": [
        "integer",
        "null"
      ],
      "description": "Vehicle model year."
    },
    "plant_city": {
      "type": [
        "string",
        "null"
      ],
      "description": "City of manufacture."
    },
    "manufacturer": {
      "type": [
        "string",
        "null"
      ],
      "description": "Name of the manufacturer."
    },
    "transmission": {
      "type": [
        "string",
        "null"
      ],
      "description": "Transmission style."
    },
    "vehicle_type": {
      "type": [
        "string",
        "null"
      ],
      "description": "Type of vehicle."
    },
    "plant_country": {
      "type": [
        "string",
        "null"
      ],
      "description": "Country of manufacture."
    },
    "decoded_variables": {
      "type": "array",
      "items": {
        "type": "object",
        "required": [
          "variable",
          "value",
          "variable_id",
          "value_id"
        ],
        "properties": {
          "value": {
            "type": [
              "string",
              "null"
            ],
            "description": "Decoded value, or null when missing."
          },
          "value_id": {
            "type": [
              "string",
              "null"
            ],
            "description": "NHTSA coded value identifier.",
            "x-fous-developer": true
          },
          "variable": {
            "type": "string"
          },
          "variable_id": {
            "type": [
              "integer",
              "null"
            ],
            "description": "NHTSA variable identifier.",
            "x-fous-developer": true
          }
        },
        "additionalProperties": false
      },
      "description": "Every decoded variable returned by NHTSA, including ones with missing values.",
      "x-fous-developer": true
    }
  },
  "additionalProperties": false
}
```

## See more

- [NHTSA API: Check vehicle recalls](https://fous.com/methods/nhtsa.gov/check-recalls.md): Lists NHTSA safety recalls for a vehicle model, given a model year, make and model or a 17-character VIN. Results cover the model, not whether a specific car has been repaired.
- [NHTSA API: Get safety ratings](https://fous.com/methods/nhtsa.gov/get-safety-ratings.md): Gets NHTSA 5-Star Safety Ratings for a car by make, model and model year. Returns each matching version; unrated versions have no stars.
- [NHTSA API: List vehicle models](https://fous.com/methods/nhtsa.gov/list-vehicle-models.md): Lists the passenger car, SUV/minivan and truck models NHTSA has for a make and model year, alphabetically.
- [NHTSA API: Get owner complaints](https://fous.com/methods/nhtsa.gov/get-owner-complaints.md): Summarizes NHTSA owner safety complaints for an exact vehicle model year, make, and model. Body-style variants are not combined; mileage is null when not given as a structured value.
- [FuelEconomy.gov API: Get fuel economy](https://fous.com/methods/fueleconomy.gov/get-fuel-economy.md): Returns official MPG or MPGe, range, annual fuel cost, five-year savings and emissions for every matching version of a vehicle. Costs use current fuel prices and 15,000 miles per year; plug-in hybrid costs include gasoline and electricity.
- [Carvana API: Search used cars](https://fous.com/methods/carvana.com/search-cars.md): Searches Carvana's used-car inventory by make and model, with optional price, year, mileage and ZIP filters, and returns each car's price, estimated monthly payment, mileage and delivery or pickup estimate for the ZIP.
- [AutoZone API: Search parts for a vehicle](https://fous.com/methods/autozone.com/search-parts.md): Finds AutoZone parts listed for a vehicle (year, make, model, optional engine), with prices, warranties and fit notes. Listings are filtered by year, make and model; engine fit often needs further confirmation.
- [FuelEconomy.gov API: Compare cars](https://fous.com/methods/fueleconomy.gov/compare-cars.md): Compares the official fuel economy and estimated annual fuel cost of two to four cars by year, make and model, using FuelEconomy.gov. Selects a base version when no trim is given.
- [All NHTSA methods](https://fous.com/methods/nhtsa.gov.md)