Price via Weight Calculation Formula For Gold Products


I’m Abhijeet Yadav. I am going to tell you about calculation for weight and size for different gold attributes such as melting, wastage, size.

For one of our web application projects being built using laravel we needed to implement cart page for gold. The cart page lists all the orders of different sellers. Each order item has melting, wastage, size, weight and price attributes associated with it. The price and weight changes with any changes in melting and size. This blog post elaborates on  calculation for price and weight under the changes in three different scenarios.


1) When Melting Changes

Base knowledge:-

In gold 24 carat is 100% gold so 1 carat is 4.167% i.e, (100/24=4.167) of gold.
So 18 carat is 18* 4.167 = 75% of gold. The same holds for all the carats of gold.


Ring size = 10, weight = 2 grms, melting = 18 carat.
Than if the buyer wants the same item in 22 carat the weight will increase by 16.60%.

Calculation (All the calculations are approx not exact):-

(22 X 4.167) – (18 X 4.167) = 16.60%.
This is standard and can be used for different melting .


2) When Size Changes


Ring size = 10, weight =  2 grms, melting =  18 carat.

The same item in size = 15, melting = 18.
It’s basic cross multiplication.

Grms                 Weight

10                       2

15                       ?

Weight = 3 grms (15X2/10)


3) When Both Melting & Size Changes

In this type of scenario whenever both melting and size changes weight is calculated as

First Weight for that particular selected melting is calculated, followed by selected size as discussed in the first two scenario

Calculation For Price

Base knowledge:-

Price of 1 grm of Gold = 2751 Rs (Assumption)

Price calculation depends on the weight of the gold.

So if the weight of the gold is 3 grms the total price will be weight multiplied by one gram of weight

(weight) X (price for 1 grm) = 3 X 2751 = 82533 rs


Calculation of 1grm of gold

In Gold there are two types of gold price


2) Hazir

The price that we get through API is RTGS which is for 99.50%. We have to convert this price for 99.99%

This is done by simple division i.e,

price = 25650/99.50X100 = 25778.89

The price above is for the 10grms of gold so 1grm = 25778.89/10=2577.88 Rs