To determine the market value of your car, you can use various online tools that provide an estimate based on factors such as the cars make, model, year, mileage, and condition. Here are some websites that offer car value estimators:

1. Kelley Blue Book: This website provides a Private Party Value report that gives a fair price when selling the car to an individual instead of doing a dealer trade-in. The values are based on actual sales transactions and auction prices, which are then analyzed and adjusted to account for seasonality and market trends.

2. Edmunds: This website offers a free appraisal tool that gives you an accurate price for your vehicle in as little as a minute. The tool provides a value based on recent data in your area and helps you understand how much you might expect to receive when you sell.

3. Consumer Reports: This website provides a trade-in value estimator that gives you an idea of what a dealer would offer for your car to apply toward the purchase of another car in the dealers inventory.

4. CarEdge: This website offers a valuation tool that provides an estimated value or offer for your car. The tool gathers quotes from various online car dealers and vehicle valuations to learn what your own car is really worth.

5. Car and Driver: This website provides a car value calculator that calculates your cars value using the same Black Book data dealers use to appraise vehicles.

Its important to note that these tools provide estimates and the actual market value of your car may vary depending on various factors such as the local market conditions, the cars condition, and the demand for the car.