Singapore License Plate - Checksum Digit Calculation

[The_chanster]

Can one of you kind souls help me on this?

 

Despite reading the Wikipedia page numerous times I still cannot derive or understand the check digit calculation of my vehicle.

 

Using the example quoted in Wiki, how do they derive the "6 fixed numbers as (9, 4, 5, 4, 3, 2)"?

and why are the 19 characters used quoted in this order?? (A, Z, Y, X, U, T, S, R, P, M, L, K, J, H, G, E, D, C, B) where A=0, Z=1, etc...

 

Can anyone make this Wiki page a lot clearer to understand for a layman?

Cheers

 

 

http://en.wikipedia.org/wiki/Vehicle_registration_plates_of_Singapore#Checksum

[F355]

OMV ARF PARF PQP Tiered ARF CEV rebates all already so difficult to understand I don't even bother about the checksum.

Edited May 31, 2014 by F355

[lausai88]

use the example: SBA 1234

 

1) ignore the letter "S"

2) B = 2, A = 1 and

3) SBA 1234 convert to 21 1234

4) Each individual number is then multiplied by 6 fixed numbers( 9, 4, 5, 4, 3, 2).

5) use convert to 21 1234 and based on the position of the number, 2 x 9, 1 x 4, 1 x 5, 2 x 4, 3 x 3, 4 x 2

6) add the numbers, 18 + 4 + 5 + 8 + 9 + 8 = 52

7) 52 divide by 19 = 2 with remainder 14

8) match with these 19 letter, A=0, Z=1, Y=2, X=3, U=4, T=5, S=6, R=7, P=8, M=9, L=10, K=11, J=12, H=13, G=14, E, D, C, B

9) remainder 14 equal to letter G

10) so SBA 1234G

[Steptronic]

Why to complicate so much leh? use the applications available in Android and Apple phones

[The_chanster]

 

4) Each individual number is then multiplied by 6 fixed numbers( 9, 4, 5, 4, 3, 2).

 

This is the bit which I don't understand. Are these numbers constants? i.e. are they used every time regardless of number plate combination?

In other words, if my number plate was SKA 1234, would I multiply (11x9, 1x4, 1x5, 2x4, 3x3, 4x2)

 

Summing up, 99+4+5+8+9+8 = 133

 

133 divided by 19 = 7

 

No remainder, so checksum is 0, (zero) = A

 

Correct logic?

[The_chanster]

I've done a quick check on the above and your method works.

Thanks lausia88. 5 points from me for your help.

[Kb27]

Calculator attached

Car Registration Calculation.xls

[Evillusion]

use the example: SBA 1234

 

1) ignore the letter "S"

2) B = 2, A = 1 and

3) SBA 1234 convert to 21 1234

4) Each individual number is then multiplied by 6 fixed numbers( 9, 4, 5, 4, 3, 2).

5) use convert to 21 1234 and based on the position of the number, 2 x 9, 1 x 4, 1 x 5, 2 x 4, 3 x 3, 4 x 2

6) add the numbers, 18 + 4 + 5 + 8 + 9 + 8 = 52

7) 52 divide by 19 = 2 with remainder 14

8) match with these 19 letter, A=0, Z=1, Y=2, X=3, U=4, T=5, S=6, R=7, P=8, M=9, L=10, K=11, J=12, H=13, G=14, E, D, C, B

9) remainder 14 equal to letter G

10) so SBA 1234G

kns....i read then i feel like i want to lausai.....hahahah

[TVT]

This is very interesting.....

 

But what purpose is this last letter in the regn plate for? What kinda of checks does it have for the authorities ?

[Alpha78]

This is very interesting.....

 

But what purpose is this last letter in the regn plate for? What kinda of checks does it have for the authorities ?

 

So that when they summon you, if the checksum doesn't tally with the number plate, you can claim that the TP pak jiao copy the wrong number.

[Kb27]

This is very interesting.....

 

But what purpose is this last letter in the regn plate for? What kinda of checks does it have for the authorities ?

 

It's a checksum, a sort of confirmation.

 

Example, if a car ran a red light and the photo is not clear or licence plate is missing a digit, you can fill in the blank conclusively like belonging to this red car, model X.

[Mockngbrd]

wow.... finally see the formula

[Crossangel]

use the example: SBA 1234

 

1) ignore the letter "S"

2) B = 2, A = 1 and

3) SBA 1234 convert to 21 1234

4) Each individual number is then multiplied by 6 fixed numbers( 9, 4, 5, 4, 3, 2).

5) use convert to 21 1234 and based on the position of the number, 2 x 9, 1 x 4, 1 x 5, 2 x 4, 3 x 3, 4 x 2

6) add the numbers, 18 + 4 + 5 + 8 + 9 + 8 = 52

7) 52 divide by 19 = 2 with remainder 14

8) match with these 19 letter, A=0, Z=1, Y=2, X=3, U=4, T=5, S=6, R=7, P=8, M=9, L=10, K=11, J=12, H=13, G=14, E, D, C, B

9) remainder 14 equal to letter G

10) so SBA 1234G

 

he deserve 100 points.. ha ha

[Jimmylim]

good for doing project which may need such info, just like the letter in our NRIC.

[Chowyunfatt]

use the example: SBA 1234

 

1) ignore the letter "S"

2) B = 2, A = 1 and

3) SBA 1234 convert to 21 1234

4) Each individual number is then multiplied by 6 fixed numbers( 9, 4, 5, 4, 3, 2).

5) use convert to 21 1234 and based on the position of the number, 2 x 9, 1 x 4, 1 x 5, 2 x 4, 3 x 3, 4 x 2

6) add the numbers, 18 + 4 + 5 + 8 + 9 + 8 = 52

7) 52 divide by 19 = 2 with remainder 14

8) match with these 19 letter, A=0, Z=1, Y=2, X=3, U=4, T=5, S=6, R=7, P=8, M=9, L=10, K=11, J=12, H=13, G=14, E, D, C, B

9) remainder 14 equal to letter G

10) so SBA 1234G

So Terror ... 👏

[Benarsenal]

use the example: SBA 1234

 

1) ignore the letter "S"

2) B = 2, A = 1 and

3) SBA 1234 convert to 21 1234

4) Each individual number is then multiplied by 6 fixed numbers( 9, 4, 5, 4, 3, 2).

5) use convert to 21 1234 and based on the position of the number, 2 x 9, 1 x 4, 1 x 5, 2 x 4, 3 x 3, 4 x 2

6) add the numbers, 18 + 4 + 5 + 8 + 9 + 8 = 52

7) 52 divide by 19 = 2 with remainder 14

8) match with these 19 letter, A=0, Z=1, Y=2, X=3, U=4, T=5, S=6, R=7, P=8, M=9, L=10, K=11, J=12, H=13, G=14, E, D, C, B

9) remainder 14 equal to letter G

10) so SBA 1234G

 

How come you know the formula ah? Never see LTA publish anywhere before leh...

[Ekiden]

Calculator attached

 

I guess the calculator only calculate S plate only right?

how about E plates?

[Kb27]

 

I guess the calculator only calculate S plate only right?

how about E plates?

 

Calculator seems to work for E plates, but the first letter you must input S, then followed by E x xxxx