warranty

Compared meaning: a written promise to repair or replace a product (noun).

比较义项：（商家或厂商就产品维修或更换所作的）书面保证（名词）。

• guarantee

  More general and informal; often implies a simple promise of quality or satisfaction, without specifying a fixed time period or legal terms.

  更笼统、更口语化；通常只是对产品质量或满意度的简单承诺，不一定说明具体期限或法律条款。

  The store offers a guarantee on all new products, but doesn't say for how long.

  这家商店对所有新产品提供保证，但没有说明期限多长。

• warranty 本词

  More formal and specific; usually a written document stating an exact time period and the conditions under which repair or replacement is covered.

  更正式、更具体；通常是一份书面文件，注明确切的期限以及维修或更换所适用的条件。

  The new washing machine comes with a two-year warranty covering parts and labor.

  这台新洗衣机附带两年保修，涵盖零件和人工费用。

Guarantee and warranty both mean a written promise to repair or replace a product. Guarantee is general and informal, a promise of quality with no fixed time period. Warranty is more formal, usually stating an exact time period. Not covered: guarantee meaning to promise something.

两个词都指产品出问题时可获维修或更换的书面承诺，但 warranty 更正式、常带明确期限，是零售和法律语境下的标准说法；guarantee 更通俗、笼统，也更常用于日常口语中表达对质量的一般承诺。这里不比较 guarantee 作“保证，担保（某事会发生）”的更宽泛义项。