Product descriptions are where merchants argue by instinct: the founder wants the origin story, the ops person wants a spec table, the copywriter read somewhere that nobody reads anything anymore. All three positions are testable, and the answer differs by store. This guide covers the description tests worth running, length, structure, benefits vs specs, storytelling, container format, and FAQ blocks, each with a hypothesis and a metric.

What a description is actually for

A product description exists to remove the reasons not to buy. Visitors arrive with questions, will this fit, will it last, is it worth the price, what exactly do I get, and the description either answers them or leaves them open. Open questions become abandoned pages.

That framing matters because it changes what “good copy” means. The best description isn’t the most elegant one; it’s the one that resolves your customers’ actual hesitations in the order they occur. Which is why testing beats taste: your audience settles the argument, not the loudest voice in the room.

Every test below uses add-to-cart rate as the primary metric, the visitor read (or scanned) the page and decided to act. It’s the standard choice for product page tests, for the reasons covered in our complete guide to Shopify A/B testing. And because copy effects are often moderate rather than dramatic, check the traffic maths before you start: an underpowered description test just produces six weeks of ambiguity. Our primer on statistical significance explains what “enough data” means in practice.

A build note: description tests are a natural fit for Shopify’s template system. Create an alternate product template (e.g. product.long-copy) with the variant description structure, and you can test it against your default without touching the live page, the full mechanics are in how to A/B test Shopify product pages.

Test 1: Long vs short

The oldest copy debate, and still worth running because the folk wisdom points both ways: “nobody reads” vs “the more you tell, the more you sell.”

Variants: your current description vs a version roughly half (or double) the length. Keep the images, price, and layout identical, length is the variable.

Hypothesis: for low-consideration products, a short, punchy description outperforms because the decision is fast and extra copy is scroll-cost. For high-consideration or novel products, longer copy wins because unanswered questions, not attention span, are what block the purchase.

Measure: add-to-cart rate. Segment by traffic source if possible: search visitors arrive with more context than cold social visitors and may need less convincing.

Honest caveat: length is a crude variable. A long description that answers real questions and a long description that waffles are different things wearing the same word count. Cut or extend with intent, and treat this test as a first pass that tells you which direction to explore.

Test 2: Wall of text vs scannable structure

Often more powerful than length itself: the same information, restructured.

Variants: flowing paragraphs vs a scannable structure, one-sentence hook, three to five benefit bullets, short “how it works” or materials section, spec table at the end.

Hypothesis: most visitors scan before deciding whether to read. A scannable structure gets your persuasive content actually consumed, so the same arguments produce more adds.

Measure: add-to-cart rate, with particular attention to mobile, paragraph walls that look acceptable on desktop become genuinely hostile on a phone screen.

This is the description test with the best effort-to-impact ratio for most stores, which is why it also appears high in our ranked list of product page A/B test ideas.

Test 3: Benefits-led vs specs-led

Not whether to include specs, you almost always should, but what leads.

Variants:

  • Benefits-led: opens with outcomes (“Stays cold for 24 hours on the trail”), specs in a table below.
  • Specs-led: opens with the facts (capacity, materials, dimensions, certifications), minimal persuasion framing.

Hypothesis: benefits-led copy wins when visitors need to be sold on why this product; specs-led wins when visitors already know what they want and are verifying whether this is it (replacement parts, technical gear, repeat-purchase consumables). Audience sophistication decides, not copywriting doctrine.

Measure: add-to-cart rate. Traffic-source segmentation is unusually informative here, comparison shoppers from non-branded search and warm email subscribers can respond in opposite directions to the same copy.

Trap to avoid: don’t strip the specs from the benefits-led variant. Missing dimension and material information doesn’t make copy more persuasive; it makes visitors leave to find the answer elsewhere.

Test 4: Storytelling and origin copy

Founder story, sourcing narrative, the problem that led to the product. Warm, differentiating, and unproven until tested.

Variants: standard descriptive copy vs a version that opens with (or weaves in) two or three sentences of genuine story: why it exists, who makes it, what it replaces.

Hypothesis: for brand-driven and gift purchases, story creates enough emotional value to lift adds. For utility purchases, it delays the information that actually converts and performs neutrally or worse.

Measure: add-to-cart rate. A story variant that draws heavy engagement but no additional adds is telling you something useful: pleasant reading isn’t purchase intent.

Keep it honest. Only tell stories that are true. Invented artisanal backstories are both ethically off and practically fragile, customers notice, and one skeptical Reddit thread outlives any conversion lift. Genuine credibility content overlaps heavily with the material in our guide to trust signals on product pages.

Test 5: Tabs vs accordion vs open text

The container question. Once you have description, specs, shipping, and care instructions, where do they live?

The candidates:

  • Open text: everything visible, page runs long, nothing hidden.
  • Tabs: compact, desktop-friendly, but content in inactive tabs is effectively invisible, many visitors never click a second tab.
  • Accordion: collapsed sections the visitor expands; the mobile-native pattern, and each opened section is a small signal of what shoppers care about.

Hypothesis: hiding content costs more than page length does, so open text (or accordions with the most decision-critical section pre-expanded) outperforms tabs, especially on mobile. The counter-case: for spec-heavy catalogues, compact containers keep the buy area near the fold and win on scannability.

Measure: add-to-cart rate, segmented by device, this is substantially a mobile layout question. If your analytics can see accordion opens, that click pattern is a free map of your customers’ real pre-purchase questions.

A note for the record: content hidden in collapsed containers is still indexed by Google, so this is a UX question rather than an SEO one, see Google’s own guidance if in doubt.

Test 6: FAQ block on the product page

The highest-leverage writing task on this list, because the material already exists in your support inbox.

Variants: current page vs the same page plus a five-to-eight question FAQ (usually an accordion below the description), answering the questions customers genuinely ask before buying: sizing, compatibility, shipping times, returns, materials, “will it work with X”.

Hypothesis: every pre-sale support email represents many more visitors who had the same question and silently left. Answering on-page converts a slice of the silent majority.

Measure: add-to-cart rate. Over the longer term, watch whether pre-sale support volume on that product declines, not a test metric, but a nice second confirmation.

Writing rule: use real questions in the customer’s own words, and answer plainly, including the awkward ones (“Will this fit a 2019 model?” “No, you need our other bracket”). An FAQ that’s obviously marketing in a trench coat converts nobody. Honest answers to hard questions are themselves a trust signal.

Running description tests without fooling yourself

Copy tests have some specific failure modes worth engineering around:

  1. Change one dimension at a time. A variant with new length and new structure and a new story teaches you which bundle won, not what to do on the other 40 products in your catalogue. Bundled rewrites are fine only when you consciously want a big-swing test.
  2. Don’t let layout smuggle itself in. If the short variant pulls reviews above the fold and the long one pushes them down, you’re testing layout too. Pin everything except the copy.
  3. Expect moderate effects and size the test accordingly. Description tests rarely produce the dramatic swings image tests can. Run whole weeks, decide the runtime in advance, and resist peeking, the maths behind that discipline is in our guide to statistical significance.
  4. Keep assignment consistent. A returning visitor who saw the story version on Tuesday shouldn’t get the spec table on Thursday, it contaminates the data and reads as sloppiness to the customer.

On the tooling side, this is where Atchoo! fits naturally: each description variant is just an alternate product template in your existing theme, visitors are deterministically assigned (same visitor, same version, every visit, via a first-party cookie), and add-to-cart rates are tracked per variant in real time with traffic-source breakdown, so you can see that the benefits-led copy lifted cold social traffic while doing nothing for email, rather than staring at a blended average. Bayesian analysis then reports the probability each variant is genuinely better, which is easier to act on than a bare p-value.

Frequently asked questions

Are long or short product descriptions better for conversion?

It depends on consideration level, and the honest answer is: test it. Low-priced, self-explanatory products tend to do fine with short copy; novel, technical, or expensive products usually benefit from longer copy because unanswered questions, not reading fatigue, are what block the add-to-cart.

Do people actually read product descriptions?

Most visitors scan first and read selectively, which argues for scannable structure (hook, bullets, spec table) rather than for writing less. The visitors who do read deeply are disproportionately the ones close to buying, so the copy serves your most valuable traffic even if the average visitor skims.

Should I use tabs or accordions for product information?

On mobile, accordions generally beat tabs, and keeping the most decision-critical content visible or pre-expanded beats hiding it in either. But container preferences vary by audience and theme, it’s a cheap template test, so run it rather than adopting anyone’s default.

Do product description changes affect SEO?

Yes, descriptions are core on-page content, so a rewrite can affect how the page ranks over time. During a properly built A/B test that isn’t a concern in the way people fear; see does A/B testing affect SEO for how Google treats tests and what to do when you ship the winner.

How do I A/B test descriptions on Shopify specifically?

Create an alternate product template with the variant copy (a template suffix like product.variant-b in your existing theme), then use a testing app to split visitors between templates and compare add-to-cart rates. The step-by-step is in how to A/B test Shopify product pages.

Stop arguing about copy in Slack and let your visitors vote. Atchoo! tests description variants as native Shopify templates, 50/50 split, real-time add-to-cart tracking, Bayesian results, on the Pro plan at $39/mo with a 14-day free trial. See pricing or start with the complete guide to Shopify A/B testing.