AI Source Index · weekly · panel v1
Which sources do the answer engines cite this week?
Every Monday Promvia asks the same 40 buyer questions to seven answer engines and records every source each answer cites. This page publishes the result: the domains that get cited, how that splits by source type, which shapes of question pull in directories, and what moved since last week. The prompt list is at the bottom so anyone can reproduce it.
This week AI Overviews cited youtube.com in 25 of 40 questions.
Week 2026-W37, measured 7 September 2026. One sample per engine per question; a difference of one or two questions is noise, not a trend.
Most-cited domains
| Domain | Questions | Type |
|---|---|---|
| youtube.com | 37 | social |
| reddit.com | 36 | community |
| forbes.com | 10 | media |
| techradar.com | 10 | media |
| cnbc.com | 6 | media |
| tomsguide.com | 6 | media |
| medium.com | 5 | other |
| rtings.com | 5 | media |
| zapier.com | 5 | other |
| dev.to | 4 | other |
| facebook.com | 4 | social |
| nerdwallet.com | 4 | media |
| blog.railway.com | 3 | other |
| emailvendorselection.com | 3 | other |
| investopedia.com | 3 | other |
Source mix
communityreferencemediadirectorysocialvendorother
Share of (question × engine) citations by source type. Bing is the organic-results proxy and is kept out of the answer-engine totals.
Directory = review, comparison and listing sites (G2, Capterra, AlternativeTo, TripAdvisor, idealo…). Media = press and review publications (Forbes, PCMag, RTINGS, Consumer Reports…). Other = retailers, vendors’ own sites and everything no rule matched.
Do directories get cited? It depends on the question's shape
| Perplexity | ChatGPT | Gemini | Claude | AI Overviews | Bing (Copilot proxy) | Google AI Mode | |
|---|---|---|---|---|---|---|---|
| best … | 0/16 | 0/16 | 1/16 | 0/16 | 0/16 | 2/16 | 0/16 |
| alternatives to … | 0/8 | 0/8 | 1/8 | 1/8 | 0/8 | 6/8 | 0/8 |
| X vs Y | 0/8 | 0/8 | 0/8 | 1/8 | 0/8 | 0/8 | 0/8 |
| how to choose … | 0/8 | 0/8 | 0/8 | 0/8 | 0/8 | 1/8 | 0/8 |
Each cell: questions of that shape whose answer cited at least one review directory, out of the questions that shape got answered. Compare the rows — the table is the finding, not a rule.
Moved since last week
Cited more
- reddit.com 33 → 36
- techradar.com 7 → 10
- blog.railway.com 1 → 3
- cnbc.com 4 → 6
- facebook.com 2 → 4
- theguardian.com 1 → 3
- activecampaign.com 1 → 2
- apps.apple.com 1 → 2
Cited less
- cnet.com 4 → 2
- quora.com 3 → 1
- tiktok.com 4 → 2
- businessinsider.com 2 → 1
- consumerreports.org 3 → 2
- cyclingweekly.com 2 → 1
- engadget.com 2 → 1
- freecodecamp.org 2 → 1
New this week
- investor.vanguard.com 0 → 2
- storyflow.so 0 → 2
- thefrontkit.com 0 → 2
- toolradar.com 0 → 2
- uptrace.dev 0 → 2
- 34devs.com 0 → 1
- 4gnews.pt 0 → 1
- 5day.io 0 → 1
Gone this week
- brevo.com 2 → 0
- clearvaluelending.com 2 → 0
- telegraph.co.uk 2 → 0
- 13labs.au 1 → 0
- 220triathlon.com 1 → 0
- aarp.org 1 → 0
- agencyhandy.com 1 → 0
- agencypro.app 1 → 0
Engine changelog
Announced by the vendor
- 2026-08-14 · — · Reddit restricts automated access to public content (AI crawlers blocked at the server)
Observed on the panel
- Bing (Copilot proxy): en.wiktionary.org 8 → 0 questions
- Bing (Copilot proxy): youtube.com 7 → 2 questions
- Bing (Copilot proxy): en.m.wiktionary.org 6 → 1 questions
An observed entry needs a move of at least 5 questions and at least half of the larger count, for one engine, between consecutive weeks. Weeks where an engine failed on more than a quarter of the panel are excluded.
Coverage
All 7 engines answered all 40 questions this week; nothing failed, nothing was skipped.
Questions this page answers
Which sources do AI answer engines cite most right now?
In the 2026-W37 measurement, across the answer engines (Bing's organic proxy excluded), the most-cited domains were youtube.com (37), reddit.com (36) and forbes.com (10), counted as the number of the 40 panel questions whose answer cited the domain at least once.
Which sources does ChatGPT cite most?
In the 2026-W37 measurement ChatGPT cited youtube.com (10), techradar.com (9) and forbes.com (6), counted over 40 fixed buyer questions with one answer per question.
Which sources does Perplexity cite most?
In the 2026-W37 measurement Perplexity cited forbes.com (4), reddit.com (4) and cnbc.com (3), counted over 40 fixed buyer questions with one answer per question.
Which sources does AI Overviews cite most?
In the 2026-W37 measurement AI Overviews cited youtube.com (25), reddit.com (20) and cnbc.com (4), counted over 40 fixed buyer questions with one answer per question.
Do AI answers cite review directories like G2, Capterra or TripAdvisor?
On this panel, 0% of all (question × engine) citations went to review, comparison or listing directories. By question shape, directories appeared in 3/112 of the ‘best …’ questions and 8/56 of the ‘alternatives to …’ questions, summed across engines.
How is the AI Source Index measured?
Forty buyer questions across eight categories are put once to each of seven answer engines every Monday through their search-grounded APIs or a SERP capture; every URL an answer cites is stored, and a domain counts once per question per engine. The prompt list is published on the page, so anyone can reproduce the run.
Method
Forty buyer questions, eight categories, four question shapes, English, no market override. Each Monday every question is put once to each of the seven engines Promvia tracks, using the same providers and prompts customers get. Every URL an answer cites is stored; a domain counts once per question per engine. Bing is classic search results, not an AI answer, and is reported separately. The panel is versioned: a prompt is never edited, only replaced under a new version.
The 40 questions
- Best CRM for a 20-person B2B startup · b2b-saas · best …
- Alternatives to Notion for team documentation · b2b-saas · alternatives to …
- Slack vs Microsoft Teams for a remote company of 50 · b2b-saas · X vs Y
- What should I look for when choosing project management software for an agency? · b2b-saas · how to choose …
- Best invoicing software for freelancers in Europe · b2b-saas · best …
- Best running shoes for flat feet · ecommerce · best …
- Alternatives to Dyson cordless vacuums that cost less · ecommerce · alternatives to …
- Shopify vs WooCommerce for a small online store · ecommerce · X vs Y
- How do I choose a standing desk for a home office? · ecommerce · how to choose …
- Best sustainable clothing brands for basics · ecommerce · best …
- Best travel insurance for a three-month trip through Southeast Asia · travel · best …
- Alternatives to Airbnb for long stays in Europe · travel · alternatives to …
- Booking.com vs Expedia for hotel prices · travel · X vs Y
- What should I check before buying a carry-on suitcase? · travel · how to choose …
- Best credit card for airline miles with no foreign transaction fee · travel · best …
- Best high-yield savings account right now · personal-finance · best …
- Alternatives to Mint for budgeting · personal-finance · alternatives to …
- Vanguard vs Fidelity for index fund investing · personal-finance · X vs Y
- How do I pick a robo-advisor? · personal-finance · how to choose …
- Best app to send money abroad with low fees · personal-finance · best …
- Best fitness tracker for sleep tracking · health-wellness · best …
- Alternatives to Peloton for home cycling · health-wellness · alternatives to …
- Headspace vs Calm for beginners · health-wellness · X vs Y
- What should I look for in a mattress for back pain? · health-wellness · how to choose …
- Best electrolyte drink for marathon training · health-wellness · best …
- Best managed Postgres hosting for a small startup · developer-tools · best …
- Alternatives to Heroku in 2026 · developer-tools · alternatives to …
- Vercel vs Netlify for a Next.js app · developer-tools · X vs Y
- How do I choose an error monitoring tool for a Node.js backend? · developer-tools · how to choose …
- Best CI service for an open source project · developer-tools · best …
- Best email marketing platform for a small e-commerce brand · marketing-tools · best …
- Alternatives to Mailchimp with better automation · marketing-tools · alternatives to …
- Semrush vs Ahrefs for keyword research · marketing-tools · X vs Y
- What should I look for in a social media scheduling tool? · marketing-tools · how to choose …
- Best landing page builder for paid ads · marketing-tools · best …
- Best noise-cancelling headphones under 300 euros · consumer-electronics · best …
- Alternatives to the Apple Watch for Android users · consumer-electronics · alternatives to …
- Kindle Paperwhite vs Kobo Clara for reading library books · consumer-electronics · X vs Y
- How do I choose a robot vacuum for a home with pets? · consumer-electronics · how to choose …
- Best budget 4K monitor for programming · consumer-electronics · best …
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