Machine Relations Index

Machine Relations Index (MRI)

Name: Machine Relations Index
Published: 2026-05-10
License: https://creativecommons.org/licenses/by/4.0/

A neutral public benchmark for how AI answer engines cite sources, built from observed root-domain citations across six engines. MRI reports citation rates by category and question type once minimum sample thresholds are met.

27,134 domains161,193 source events20,821 answer runs103/151 measurable segments validated

Measurement window2026-05-10 to 2026-10-04

Published 2026-10-04 from the current dataset release covering 27,134 cited domains and 161,193 source events.

Sample threshold10/7

Rates publish after enough answer runs across distinct observation dates.

Segment coverage68.2%

103 of 151 measurable segments validated, 48 still collecting observations. A further 6 of the 157 segments in the full universe cannot accumulate evidence and are excluded from every rate.

Citation leaders

Top cited domains

Reddit#1 overall · Community and social platform100th percentile overall · 2,264 cited runs · 4 engines YouTube#2 overall · Search or media platform100th percentile overall · 1,599 cited runs · 6 engines LinkedIn#3 overall · Community and social platform100th percentile overall · 1,290 cited runs · 6 engines Medium#4 overall · Community and social platform100th percentile overall · 889 cited runs · 6 engines Forbes#1 of 1594 classified editorial publications · Editorial publication100th percentile overall · 856 cited runs · 6 engines Arxiv.org#6 overall · Academic and government source100th percentile overall · 611 cited runs · 6 engines TechRadar#2 of 1594 classified editorial publications · Editorial publication100th percentile overall · 594 cited runs · 4 engines G2#8 overall · Market and company database100th percentile overall · 567 cited runs · 6 engines

Source universe

Cited source index

Initial view shows the top 50 domains from 27,134 total.

Data through 2026-10-04

Row	Source	Class			Confidence
1	Redditreddit.com · #1 of 27,134 observed domains · source site	Community and social platform	10.87%	2,264	Confidence A
2	YouTubeyoutube.com · #2 of 27,134 observed domains · source site	Search or media platform	7.68%	1,599	Confidence A
3	LinkedInlinkedin.com · #3 of 27,134 observed domains · source site	Community and social platform	6.20%	1,290	Confidence A
4	Mediummedium.com · #4 of 27,134 observed domains · source site	Community and social platform	4.27%	889	Confidence A
5	Forbesforbes.com · #1 of 1594 classified editorial publications · source site	Editorial publication	4.11%	856	Confidence A
6	Arxiv.orgarxiv.org · #6 of 27,134 observed domains · source site	Academic and government source	2.93%	611	Confidence A
7	TechRadartechradar.com · #2 of 1594 classified editorial publications · source site	Editorial publication	2.85%	594	Confidence A
8	G2g2.com · #8 of 27,134 observed domains · source site	Market and company database	2.72%	567	Confidence A
9	NIHnih.gov · #9 of 27,134 observed domains · source site	Academic and government source	2.72%	567	Confidence A
10	Gartner.comgartner.com · #10 of 27,134 observed domains · source site	Analyst and consulting research	2.42%	503	Confidence A
11	Yahoo Newsyahoo.com · #3 of 1594 classified editorial publications · source site	Editorial publication	1.95%	406	Confidence A
12	Microsoft.commicrosoft.com · #12 of 27,134 observed domains · source site	Vendor-owned source	1.86%	387	Confidence A
13	Healthline.comhealthline.com · #4 of 1594 classified editorial publications · source site	Editorial publication	1.73%	360	Confidence B
14	Ibm.comibm.com · #14 of 27,134 observed domains · source site	Vendor-owned source	1.66%	346	Confidence A
15	Amazon.comamazon.com · #15 of 27,134 observed domains · source site	Other observed source	1.62%	337	Confidence A
16	TechTargettechtarget.com · #5 of 1594 classified editorial publications · source site	Editorial publication	1.48%	309	Confidence A
17	Nerdwallet.comnerdwallet.com · #6 of 1594 classified editorial publications · source site	Editorial publication	1.48%	308	Confidence A
18	Landbase.comlandbase.com · #18 of 27,134 observed domains · source site	Vendor-owned source	1.45%	301	Confidence A
19	Crunchbase.comcrunchbase.com · #19 of 27,134 observed domains · source site	Market and company database	1.34%	278	Confidence B
20	Substack.comsubstack.com · #20 of 27,134 observed domains · source site	Community and social platform	1.33%	277	Confidence B
21	Dev.todev.to · #21 of 27,134 observed domains · source site	Community and social platform	1.32%	275	Confidence B
22	Paloaltonetworks.compaloaltonetworks.com · #22 of 27,134 observed domains · source site	Vendor-owned source	1.29%	268	Confidence B
23	Guideflow.comguideflow.com · #23 of 27,134 observed domains · source site	Vendor-owned source	1.24%	258	Confidence B
24	Sentinelone.comsentinelone.com · #24 of 27,134 observed domains · source site	Vendor-owned source	1.12%	234	Confidence B
25	Wikipediawikipedia.org · #25 of 27,134 observed domains · source site	Academic and government source	1.11%	231	Confidence B
26	Facebook.comfacebook.com · #26 of 27,134 observed domains · source site	Community and social platform	1.10%	229	Confidence B
27	Hubspot.comhubspot.com · #27 of 27,134 observed domains · source site	Vendor-owned source	1.04%	216	Confidence B
28	Github.comgithub.com · #28 of 27,134 observed domains · source site	Community and social platform	1.03%	214	Confidence B
29	Nytimes.comnytimes.com · #7 of 1594 classified editorial publications · source site	Editorial publication	0.98%	204	Confidence B
30	PR Newswireprnewswire.com · #30 of 27,134 observed domains · source site	Wire and press-release distribution	0.97%	203	Confidence B
31	Deloitte.comdeloitte.com · #31 of 27,134 observed domains · source site	Analyst and consulting research	0.97%	201	Confidence B
32	Zapier.comzapier.com · #32 of 27,134 observed domains · source site	Vendor-owned source	0.93%	193	Confidence B
33	Grandviewresearch.comgrandviewresearch.com · #33 of 27,134 observed domains · source site	Market and company database	0.91%	189	Confidence B
34	Peoplemanagingpeople.compeoplemanagingpeople.com · #8 of 1594 classified editorial publications · source site	Editorial publication	0.91%	189	Confidence B
35	PCMagpcmag.com · #9 of 1594 classified editorial publications · source site	Editorial publication	0.88%	183	Confidence B
36	Stripe.comstripe.com · #36 of 27,134 observed domains · source site	Vendor-owned source	0.86%	180	Confidence B
37	Experian.comexperian.com · #37 of 27,134 observed domains · source site	Vendor-owned source	0.85%	176	Confidence B
38	Cnbc.comcnbc.com · #10 of 1594 classified editorial publications · source site	Editorial publication	0.83%	173	Confidence B
39	Harvard.eduharvard.edu · #39 of 27,134 observed domains · source site	Academic and government source	0.83%	173	Confidence B
40	Nvidia.comnvidia.com · #40 of 27,134 observed domains · source site	Vendor-owned source	0.82%	170	Confidence B
41	TechCrunchtechcrunch.com · #11 of 1594 classified editorial publications · source site	Editorial publication	0.82%	170	Confidence B
42	Y Combinatorycombinator.com · #42 of 27,134 observed domains · source site	Community and social platform	0.81%	169	Confidence B
43	Bankrate.combankrate.com · #43 of 27,134 observed domains · source site	Other observed source	0.81%	168	Confidence B
44	Rippling.comrippling.com · #44 of 27,134 observed domains · source site	Vendor-owned source	0.81%	168	Confidence B
45	Alibaba.comalibaba.com · #45 of 27,134 observed domains · source site	Other observed source	0.80%	167	Confidence B
46	Databricks.comdatabricks.com · #46 of 27,134 observed domains · source site	Vendor-owned source	0.80%	167	Confidence B
47	Fortunebusinessinsights.comfortunebusinessinsights.com · #47 of 27,134 observed domains · source site	Market and company database	0.78%	162	Confidence B
48	Erpresearch.comerpresearch.com · #48 of 27,134 observed domains · source site	Market and company database	0.73%	152	Confidence B
49	Salesforce.comsalesforce.com · #49 of 27,134 observed domains · source site	Vendor-owned source	0.73%	152	Confidence B
50	Semrush.comsemrush.com · #50 of 27,134 observed domains · source site	Vendor-owned source	0.73%	152	Confidence B

Agent access

Use this data in your agent

Every figure on this index can be read by machines. The MCP endpoint and the REST API return the same domain, category and segment records you see here. Each record carries its release identifier, window and denominators, and segment records also carry the evidence floor, so an agent can cite the exact number and when it was measured. The data is published under CC BY 4.0.

Read a segment rank as a statement about the questions behind it, not about a whole market. Some segments rest on only a few questions, and published rates still include runs where the question names the domain's own brand. Pulling from the API reproduces the published numbers; it does not re-run the measurement.

MCP endpoint: https://machinerelations.ai/mcp

The Machine Relations Index measures how often AI answer engines cite each source domain when people ask real buying and research questions. It observes six engines — Perplexity, ChatGPT, Gemini, Claude, Google AI Mode, and Google AI Overviews — across a fixed basket of 24 measured subject categories plus a legacy news-topic bucket (25 taxonomy nodes in all). Findings are grouped into strata, where a stratum is one subject category paired with one question type. A stratum publishes a citation rate only after it clears the evidence floor of at least 10 observed runs across at least 7 distinct dates; below that line it is marked collecting rather than scored, so early or thin signal is never shown as settled. Every domain an engine cites is measured on equal terms — membership in any external catalog is recorded only as a label and is never used to decide what gets scored. The public Index reports rates and rankings; it excludes raw cited URLs, internal query identifiers, and provider payloads. Validated source segments currently cover 68.2% of the measurable benchmark, which is the 151 segments that can accumulate evidence out of 157 in the full stratum universe.

Release mri_score_v2.0+2026-10-04+1a1218e0e1ed. All 6 answer engines are currently returning answers. Coverage across the window is uneven: gemini answered on 119 of 141 observed days (1,943 of 4,531 returned runs produced a citation); google_ai_mode answered on 99 of 141 observed days (1,311 of 1,643 returned runs produced a citation); google_ai_overviews answered on 82 of 141 observed days (709 of 1,141 returned runs produced a citation). Engines below 90% of the window are named here; per-engine day and run counts for all 6 are in engine_roster.

Machine Relations Index (MRI)

Top cited domains

Cited source index

Use this data in your agent

Check how AI systems cite your brand.