Outstanding means exceptionally good; astounding means shockingly impressive. Key Differences Outstanding refers to something exceptionally good, noticeable, or prominent, while astounding implies something is surprisingly impressive or causes a great amount of amazement.

While both terms are complimentary, the choice between astounding and outstanding depends on the context and the nature of what is being described. Astounding emphasizes the shock and amazement factor, while outstanding emphasizes a high standard of excellence and quality that sets someone or something apart from the rest.