Usually there is some confusion about when to use “whether” and when to use “if”. Although it seems that they are used interchangeably in informal speech, there is a difference in their usage especially when you are writing.
According to the Oxford dictionary “whether” is a conjunction which has the following definitions.
- Expressing a doubt or choice between alternatives.
‘he seemed undecided whether to go or stay’
‘it is still not clear whether or not he realizes’
1.1 Expressing an enquiry or investigation (often used in indirect questions)
‘I’ll see whether she’s at home’
1.2 Indicating that a statement applies whichever of the alternatives mentioned is the case.
‘I’m going whether you like it or not’
“Whether” is used when the sentence either states an alternative or implies an alternative. “If” is used in a sentence that indicates a condition. Here is an example of the use of “whether”.
Examples:
- You will have a test tomorrow whether on French or Spanish grammar I will not disclose.
- Whether the weather is dry or rainy my road is usually impassable.
In the sentences above the alternatives are clearly stated so you would use “whether”.
In sentence 1 above it is clearly impossible to use “if” in place of “whether”. The second sentence provides a good example to show that although it seems possible to use “if” that would be incorrect because alternatives are clearly stated and there is no condition stated.
Use of “if”
Examples:
- The mayor will fix the roads if he collects enough tax revenue.
- If the high surf continues the boats will be wrecked.
In these sentences above we use “if” because each sentence includes a condition.
Use of “whether or not”
“Whether or not” is used when the action will be taken regardless of the choices.
I am going to university whether or not I get a scholarship.
Remember to use “whether” when there are clear or implied alternatives.
Use “if” when there are conditions.