tire

Tire Size Calculator

Calculate tire sizes in inches or millimeters and find alternative sizes.
Tread Width: 325
  • 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 325/30R21 Tires

disc wheel
Diameter
28.7"
tire width
Width
12.8"
disc wheel
Sidewall
3.8"
tire circumference
Circumference
90"
tire rpm
Revs per mile
704
        

            

                
Alternate Tire Sizes

                

                

                                            

                            

                                21"
                            

                        
                    
                                                                        

                                    

                                        15"
                                    

                                

                                                            

                                    

                                        16"
                                    

                                

                                                            

                                    

                                        17"
                                    

                                

                                                            

                                    

                                        18"
                                    

                                

                                                            

                                    

                                        19"
                                    

                                

                                                            

                                    

                                        20"
                                    

                                

                                                            

                                    

                                        22"
                                    

                                

                                                            

                                    

                                        23"
                                    

                                

                                                            

                                    

                                        24"
                                    

                                

                                            

                

                    

                                                    

                                

                                    
Tire Size

                                    
Diameter

                                    
Width

                                    
Sidewall

                                    
Circumference

                                    
Revs per mile

                                    

                                

                                                                
255/35R21
                                                
                                                    
                                                        
                                                            
                                                            
                                                            
                                                            
                                                        
                                                    
                                                
                                            
28,0"
-2.5%
10,0"
3,5"
88,0"
720
295/30R21
                                                
                                                    
                                                        
                                                            
                                                            
                                                            
                                                            
                                                        
                                                    
                                                
                                            
28,0"
-2.5%
11,6"
3,5"
87,8"
722
355/25R21
                                                
                                                    
                                                        
                                                            
                                                            
                                                            
                                                            
                                                        
                                                    
                                                
                                            
28,0"
-2.5%
14,0"
3,5"
87,9"
721
305/30R21
                                                
                                                    
                                                        
                                                            
                                                            
                                                            
                                                            
                                                        
                                                    
                                                
                                            
28,2"
-1.77%
12,0"
3,6"
88,6"
715
265/35R21
                                                
                                                    
                                                        
                                                            
                                                            
                                                            
                                                            
                                                        
                                                    
                                                
                                            
28,3"
-1.41%
10,4"
3,7"
88,9"
713
315/30R21
                                                
                                                    
                                                        
                                                            
                                                            
                                                            
                                                            
                                                        
                                                    
                                                
                                            
28,4"
-1.06%
12,4"
3,7"
89,3"
710
275/35R21
                                                
                                                    
                                                        
                                                            
                                                            
                                                            
                                                            
                                                        
                                                    
                                                
                                            
28,6"
-0.35%
10,8"
3,8"
89,7"
706

                                                    
                                                        
                                                            
                                                                
                                                                
                                                            
                                                        
                                                    
                                                Best fit
245/40R21
                                                
                                                    
                                                        
                                                            
                                                            
                                                            
                                                            
                                                        
                                                    
                                                
                                            
28,7"
0%
9,6"
3,9"
90,2"
703

                                                    
                                                        
                                                            
                                                                
                                                                
                                                            
                                                        
                                                    
                                                Best fit
325/30R21
                                                
                                                    
                                                        
                                                            
                                                            
                                                            
                                                            
                                                        
                                                    
                                                
                                            
28,7"
0%
12,8"
3,8"
90,0"
704

                                                    
                                                        
                                                            
                                                                
                                                                
                                                            
                                                        
                                                    
                                                Best fit
335/30R21
                                                
                                                    
                                                        
                                                            
                                                            
                                                            
                                                            
                                                        
                                                    
                                                
                                            
28,9"
0.69%
13,2"
4,0"
90,8"
698

                                                    
                                                        
                                                            
                                                                
                                                                
                                                            
                                                        
                                                    
                                                Best fit
285/35R21
                                                
                                                    
                                                        
                                                            
                                                            
                                                            
                                                            
                                                        
                                                    
                                                
                                            
28,9"
0.69%
11,2"
3,9"
90,6"
699

                                                    
                                                        
                                                            
                                                                
                                                                
                                                            
                                                        
                                                    
                                                Best fit
255/40R21
                                                
                                                    
                                                        
                                                            
                                                            
                                                            
                                                            
                                                        
                                                    
                                                
                                            
29,0"
1.03%
10,0"
4,0"
91,2"
695
295/35R21
                                                
                                                    
                                                        
                                                            
                                                            
                                                            
                                                            
                                                        
                                                    
                                                
                                            
29,1"
1.37%
11,6"
4,1"
91,5"
693
265/40R21
                                                
                                                    
                                                        
                                                            
                                                            
                                                            
                                                            
                                                        
                                                    
                                                
                                            
29,3"
2.05%
10,4"
4,2"
92,1"
688
235/45R21
                                                
                                                    
                                                        
                                                            
                                                            
                                                            
                                                            
                                                        
                                                    
                                                
                                            
29,3"
2.05%
9,3"
4,2"
92,1"
688
305/35R21
                                                
                                                    
                                                        
                                                            
                                                            
                                                            
                                                            
                                                        
                                                    
                                                
                                            
29,4"
2.38%
12,0"
4,2"
92,3"
686