Agotador vs. cansador

In Spanish language, there are numerous synonyms for common English words. Two such synonyms are 'agotador' and 'cansador', both translating approximately to 'exhausting' or 'tiring' in English. While they’re indeed related, they carry subtle differences that could change the meaning of a sentence.

Agotador

This word is generally used when referring to something that is extremely wearying or draining, often to the point of exhaustion. It can be used in both physical and metaphorical contexts.
El trabajo físico puede ser agotador.
(Physical work can be exhausting.)
Un día entero de compras es realmente agotador.
(A whole day of shopping is really exhausting.)

Cansador

This word tends to refer to something which is merely tiring or fatiguing, but not necessarily to the point of complete exhaustion as with 'agotador'. It usually implies a lower level of tiredness compared to 'agotador'.
El camino cuesta arriba es cansador, pero vale la pena por la vista.
(The uphill path is tiring, but worth it for the view.)
El ruido constante de la ciudad puede ser cansador.
(The constant noise of the city can be tiring.)

Summary

While 'agotador' and 'cansador' both convey the sense of being tiring or exhaustive, 'agotador' suggests a higher degree of exhaustion, often to the point where one's resources are depleted. On the other hand, 'cansador' implies less severe tiredness or fatigue.