How do I write product comparison copy without implying unsupported differences?

Start by separating the comparison into three things: the criteria, the evidence, and the wording. Decide which attributes genuinely help the reader choose—such as listed dimensions, included items, or a stated service term—and define exactly what each criterion means. Then use the same criteria for every option. Organize the comparison around evidence, not around a conclusion you want the reader to reach. General writing guidance supports evaluating evidence and keeping sections focused; it does not provide a product-specific comparison standard. [S1]

Before drafting, make a working table with a claim-verification column. For each cell, note the exact source you checked, what it says, and whether the proposed wording stays within it. Check specific facts against evidence and avoid presenting opinion as fact. [S3] If you cannot verify a difference, don’t imply one.

Choose criteria based on the reader’s decision, not on which features make a preferred product look strongest. Write a short definition beside each criterion. For example, “battery life” could mean a maker’s stated maximum, a measured result under a specified test, or something else; don’t put those different kinds of information in one row as if they were equivalent.

Include a criterion only when you can apply its definition to each option, or when you can clearly mark gaps. If one product description says “up to 10 hours” and another provides no figure, record the first as stated and the second as “not provided”—not as zero, shorter, or worse. If figures use different methods or definitions, label them “not directly comparable.” Don’t infer that an unlisted feature is absent.

Use one verification entry per product-and-criterion claim. Capture the wording you intend to publish, the source or document checked, the relevant passage or location, the check date if useful to your process, and a status such as “verified,” “needs confirmation,” or “not comparable.” A status is a drafting aid, not proof on its own; the evidence must support the exact claim. If sources conflict, pause the claim for resolution rather than choosing the more favorable version.

Here is a hypothetical worksheet using invented product labels and assumed descriptions—not claims about real products:

Draft wording: “Product A lists a maximum of up to 10 hours. The checked description for Product B does not provide a battery-life figure.” This reports what each description says without claiming a real-world performance difference. If you cannot identify what was checked, use a placeholder and hold the claim rather than making the source sound more specific than it is.

Make the takeaway conditional on the reader’s stated priority. For example: “If a published battery-life figure is important to you, Product A’s checked description provides one; Product B’s checked description does not. That alone does not establish which product lasts longer in use.” This distinguishes a documented difference in the descriptions from a conclusion about performance.

Before publication, reread every comparative word—such as “longer,” “faster,” “more durable,” “best,” or “cheaper.” Ask what evidence supports the comparison, whether the same definition and basis apply to both options, and whether the sentence goes beyond that evidence. General source-evaluation guidance recommends checking whether evidence supports a claim and cross-checking specific facts. [S3] It does not establish that any particular product claim is accurate; that depends on the evidence you actually review.

If presenting the finished comparison as a web table, make sure relationships between headers and data cells are clear to assistive technology. Accessibility guidance addresses table structure, not whether the product claims are true. [S2]