PASSIM vs VellumUp: On‑Brand SEO Content
Two Shopify apps, side by side: detected stores, momentum, reviews, plans, listed features and who runs each. Store counts as of Oct 13, 2026 for PASSIM, Oct 28, 2026 for VellumUp.
The short answer
- Only VellumUp lists a free plan. Paid plans start at $99/month for PASSIM and $79/month for VellumUp.
- PASSIM lists 7 features VellumUp’s listing doesn’t mention, including Competitor analysis, JSON-LD, Metadata optimization.
Head to head
Starter
- · 100% async — no calls, ever
- · 30 AEO-optimized articles per month
- · 50 tracked queries probed daily
- · Auto-publishes to your Shopify blog
- · Brand voice trained from your site
- · Charged on your Shopify bill — no card
Growth
- · 2 extra AI engines (Claude, Gemini)
- · 250 tracked queries probed daily
- · AI citation dashboard in real time
- · All Starter features, plus:
- · Custom blog subdomain
- · Question research from 5 sources
Scale
- · 500 tracked queries probed daily
- · All Growth features, plus:
- · Auto-publish to Shopify, WordPress, etc
- · Up to 2 sites under one account
Free
- · 1 Keyword Opportunity Scan
- · 1 Website
- · 50 Credits — one-time
- · Monthly content plan
- · Up to 5 Optimized Articles
Grow
- · 1 Website
- · 350 Credits / month
- · Auto-planning & publishing
- · Monthly Keyword Opportunity Scan
- · Up to 35 Optimized Articles
Scale
- · 1,100 Credits / month
- · Auto-planning & publishing
- · Bi-weekly Keyword Opportunity Scan
- · Up to 110 Optimized Articles
- · Up to 3 Websites
Coverage counts what each App Store listing names. Every feature, checked off app by app, is in Shoplist.
See every featureBuyers ask ChatGPT before they Google. If your brand isn't cited in AI answers, you're invisible when they decide. PASSIM installs to your Shopify store, extracts your brand voice, and auto-publishes one 1,800+ word article a day to your blog — engineered to be cited by ChatGPT, Perplexity, Claude, Gemini, and Google AI Overviews. Insights dashboard tracks your citations across every engine, daily. No calls.
Writing consistent, SEO-optimized blog content takes time most merchants don't have. VellumUp studies your store and existing content to learn your brand's voice, then researches keywords and topics relevant to your business. It writes full articles in that voice, structured for both search engines and AI assistants, and publishes them directly to your Shopify blog.
- Daily long-form articles written to be cited by ChatGPT and Perplexity.
- Brand voice and theme matched — articles look native to your existing blog.
- Track citations across ChatGPT, Perplexity, Claude, and Google AI Overviews.
- Deep-scans your site's structure, links, and brand voice, then writes to match
- Researches keywords and topics relevant to your store
- Automatically plans and publishes new articles on a schedule
- Articles are built to rank on Google and get cited by AI
All the numbers
Every figure, side by side
A green dot marks the app ahead on a measured figure. Estimates, gaps and apps that leave no storefront trace never take the lead.
Adoption
| Measure |  PASSIM |  VellumUp |
|---|---|---|
| Detected stores | Not published | Not published |
| Net store change, 28 days | 0 | 0 |
| Stores added, 28 days | Not enough data | Not enough data |
| Big-brand share | Not enough data | Not enough data |
| Top store categories | Not published | Not published |
| Top store countries | Not published | Not published |
Reviews
| Measure | PASSIM | VellumUp |
|---|---|---|
| App Store rating | Not published | Not published |
| App Store reviews | Not published | Not published |
| New reviews, 28 days | Not enough data | Not enough data |
| Reviewers a year or more in | Not enough data | Not enough data |
FAQ
PASSIM and VellumUp: common questions
- Is PASSIM or VellumUp cheaper?
- Only VellumUp lists a free plan. Paid plans start at $99/month for PASSIM and $79/month for VellumUp. Shoplist compares base prices only between monthly plans in the same currency; usage charges and annual plans vary, so check each plan’s limits.
- What features does each app list that the other doesn’t?
- PASSIM lists 7 the others don’t mention, such as Competitor analysis, JSON-LD, Metadata optimization, Page indexing. VellumUp lists 5 the others don’t mention, such as APIs and webhooks, Automations, Image optimization, Keyword analysis. A feature missing from a listing may still be supported; this compares what each App Store listing says.
- Where does this comparison’s data come from?
- Shoplist crawls Shopify storefronts to detect which apps each store runs, and reads each app’s Shopify App Store listing for reviews, pricing, features and integrations. Store counts are as of Oct 13, 2026 for PASSIM, Oct 28, 2026 for VellumUp; estimated figures are labeled.
How Shoplist compares apps
Store counts come from Shoplist’s crawl of Shopify storefronts, which detects the apps each store runs; they are as of Oct 13, 2026 for PASSIM, Oct 28, 2026 for VellumUp. Reviews, ratings, plans, features and integrations come from each app’s Shopify App Store listing. 28-day figures are labeled when estimated, and a figure that is missing or estimated never decides who leads. Read the methodology.