Less vs. Least

'Less' and 'least' are used a lot in English so it is important to know their differences. Let's dive right into it.

What Are Their Main Differences?

'Less' refers to a small amount, while '(the) least' refers to the smallest amount or number.
They are the superlative and comparative forms of the adjective 'little'.

	comparative	superlative
little	less	more
many	the least	the most

Grammatical Functions

Both of these words can be used as:

Determiners (As determiners, they are used before nouns.)
Pronouns (As pronouns can be used without a noun or they are not immediately followed by a noun.)
Adverbs (As adverbs, they are used before adjectives or adverbs or even after verbs to define them.)

Difference as Determiners

'Less' and 'the least are followed by a singular uncountable noun.

They waste less money than they did before.

I haven't the least idea what you are talking about.

Tip!

Some grammarians recommend using 'least' only with uncountable nouns. With plural nouns, they recommend 'the fewest'. However, other authorities disagree.

One of the least ~~points~~ was mine. → One of the fewest points was mine.

Difference as Pronouns

Both can be used without nouns after them as pronouns:

Most of us got £4 an hour, but some received even less.

The least you could do is give me her phone number.

Difference as Adverbs

They both can be used before adjectives in order to make a comparative and superlative form of that adjective.

I was least concerned with it. (superlative)

I was less concerned with it. (comparative)

They can also be used after verbs to modify them.

Maybe he would worry less if he understood the situation. (comparative)

Maybe he would worry the least if he understood the situation. (superlative)

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