The old way I learned was for every 10 pounds you weigh- you eat 100 calories. So if you weigh 200 pounds you can eat 2000 and maintain your weight.
For you I'd say if you are 281 and want to lose weight you eat 75% of your maintenance calories to lose weight- so it's 281 x 10 x .75 = 2100 calories to lose weight.
As you lose more weight you should recalculate those numbers
