What is the difference between the estimator and the quantity surveyor?

Estimator - responsible for estimating the direct and indirect cost of project during tendering. This role end after handover of project to execution team after award.

QS - responsible for providing accurate BOQ, checking quantites against rawings and providing inputs for Direct cost of the project. This role can continue during execution of project.

it's like, before delivery the baby and after delivery. The estimator is responsible only up to delivery period, after the Quantity surveyor is responsible for entire life span.

The Estimators should have a vast knowledge about the project while pricing for a Tender he is the initial person giving the total cost for a project during tender stage and playing in costs to get more profit. The Quantity Surveyor is working based on his pricing after award of the project and working to increase the profit for the company than the estimated cost by the Estimator. 

Better to be an Estimator & Quantity Surveyor

An experienced quantity surveyor can estimate a project in a more appropriate and fashion

estimator is the one who can estimate the cost of the project items .

the quantity surveyor is the one who calculate the quantity of the project items

Estimator is respensible for estimate the cost of project before  lauching of tender. But Quantity Surveyor will check the quantities in the execution of Project to pay the cocontractor company for what will be done, takes into account the budget of Contract.  if there  additionel work He must contact the Contract Authority to do amendment with respect to Public Procurment Code.

In my opinion, it is better to wrok as an estimator & quantity Surveyor at the same time

Briefly we can say, Estimator job is in the pre-tendering part and quantity surveyor job is in post tendering part.

basicaly purchaser and checker

The estimator calculates the quantum of work & its cost before tendering or before start of particular project. Estimator needs vast technical & commercial knowledge to ensure profits.

While quantity surveyor work starts after award of work i.e. in project execution stage whose aim is to calculate & keep accounts of actual quantity and cost of material, labour & equipments used to maximize profits.

Estimator is one who test the availability of the production where as qulity surveyor is one who test whether the product's quality or the quality of the production process

Is the estimated cost will be as same/accurate during tendering and at the time of execution.