tire

Tire Size Calculator

Calculate tire sizes in inches or millimeters and find alternative sizes.
Tread Width: 285
  • 125
  • 130
  • 145
  • 155
  • 165
  • 175
  • 185
  • 195
  • 205
  • 215
  • 225
  • 235
  • 245
  • 255
  • 265
  • 275
  • 285
  • 295
  • 305
  • 315
  • 325
  • 335
  • 345
  • 355
  • 365
Aspect Ratio: 30
  • 20
  • 25
  • 30
  • 35
  • 40
  • 45
  • 50
  • 55
  • 60
  • 65
  • 70
  • 75
  • 80
  • 85
  • 90
  • 95
Wheel Diameter: 21
  • 12
  • 13
  • 14
  • 15
  • 16
  • 17
  • 18
  • 19
  • 20
  • 21
  • 22
  • 23
  • 24
  • 25
  • 26
  • 27
  • 28
Inches
Millimeters

Results for 285/30R21 Tires

disc wheel
Diameter
27.7"
tire width
Width
11.2"
disc wheel
Sidewall
3.4"
tire circumference
Circumference
87.1"
tire rpm
Revs per mile
728
        

            

                
Alternate Tire Sizes

                

                

                                            

                            

                                21"
                            

                        
                    
                                                                        

                                    

                                        14"
                                    

                                

                                                            

                                    

                                        15"
                                    

                                

                                                            

                                    

                                        16"
                                    

                                

                                                            

                                    

                                        17"
                                    

                                

                                                            

                                    

                                        18"
                                    

                                

                                                            

                                    

                                        19"
                                    

                                

                                                            

                                    

                                        20"
                                    

                                

                                                            

                                    

                                        22"
                                    

                                

                                            

                

                    

                                                    

                                

                                    
Tire Size

                                    
Diameter

                                    
Width

                                    
Sidewall

                                    
Circumference

                                    
Revs per mile

                                    

                                

                                                                
255/30R21
                                                
                                                    
                                                        
                                                            
                                                            
                                                            
                                                            
                                                        
                                                    
                                                
                                            
27,0"
-2.59%
10,0"
3,0"
84,9"
747
305/25R21
                                                
                                                    
                                                        
                                                            
                                                            
                                                            
                                                            
                                                        
                                                    
                                                
                                            
27,0"
-2.59%
12,0"
3,0"
84,8"
747
265/30R21
                                                
                                                    
                                                        
                                                            
                                                            
                                                            
                                                            
                                                        
                                                    
                                                
                                            
27,3"
-1.47%
10,4"
3,1"
85,6"
740
325/25R21
                                                
                                                    
                                                        
                                                            
                                                            
                                                            
                                                            
                                                        
                                                    
                                                
                                            
27,4"
-1.09%
12,8"
3,2"
86,0"
737
275/30R21
                                                
                                                    
                                                        
                                                            
                                                            
                                                            
                                                            
                                                        
                                                    
                                                
                                            
27,5"
-0.73%
10,8"
3,2"
86,3"
734

                                                    
                                                        
                                                            
                                                                
                                                                
                                                            
                                                        
                                                    
                                                Best fit
285/30R21
                                                
                                                    
                                                        
                                                            
                                                            
                                                            
                                                            
                                                        
                                                    
                                                
                                            
27,7"
0%
11,2"
3,4"
87,1"
728

                                                    
                                                        
                                                            
                                                                
                                                                
                                                            
                                                        
                                                    
                                                Best fit
245/35R21
                                                
                                                    
                                                        
                                                            
                                                            
                                                            
                                                            
                                                        
                                                    
                                                
                                            
27,8"
0.36%
9,6"
3,4"
87,1"
727

                                                    
                                                        
                                                            
                                                                
                                                                
                                                            
                                                        
                                                    
                                                Best fit
345/25R21
                                                
                                                    
                                                        
                                                            
                                                            
                                                            
                                                            
                                                        
                                                    
                                                
                                            
27,8"
0.36%
13,6"
3,4"
87,3"
726

                                                    
                                                        
                                                            
                                                                
                                                                
                                                            
                                                        
                                                    
                                                Best fit
355/25R21
                                                
                                                    
                                                        
                                                            
                                                            
                                                            
                                                            
                                                        
                                                    
                                                
                                            
28,0"
1.07%
14,0"
3,5"
87,9"
721
255/35R21
                                                
                                                    
                                                        
                                                            
                                                            
                                                            
                                                            
                                                        
                                                    
                                                
                                            
28,0"
1.07%
10,0"
3,5"
88,0"
720
295/30R21
                                                
                                                    
                                                        
                                                            
                                                            
                                                            
                                                            
                                                        
                                                    
                                                
                                            
28,0"
1.07%
11,6"
3,5"
87,8"
722
305/30R21
                                                
                                                    
                                                        
                                                            
                                                            
                                                            
                                                            
                                                        
                                                    
                                                
                                            
28,2"
1.77%
12,0"
3,6"
88,6"
715
265/35R21
                                                
                                                    
                                                        
                                                            
                                                            
                                                            
                                                            
                                                        
                                                    
                                                
                                            
28,3"
2.12%
10,4"
3,7"
88,9"
713
315/30R21
                                                
                                                    
                                                        
                                                            
                                                            
                                                            
                                                            
                                                        
                                                    
                                                
                                            
28,4"
2.46%
12,4"
3,7"
89,3"
710