What model powers Perplexity?
The answer engine that cites its sources on almost every query.
As of July 2026, Perplexity’s free default answers with Sonar — its in-house model, built on Llama and tuned for cited, retrieval-first search. Perplexity routes the default search experience to Sonar automatically; subscribers can switch to other frontier models. Discoverably reads the model from Perplexity’s own answers, so this tracks the default your customers get, not a paid arm they’d have to choose.
- Current model
- Sonar
- Evidence
- Observed
- As of
- Feb 2025
- What we capture
- perplexity.ai, the free default
Discoverably reads this model from the engine’s own answers, so it reflects what the free experience actually returns — not only what the vendor last announced.
How Perplexity picks its model
Perplexity is the most retrieval-first engine we track: it runs a live web search on essentially every query and composes the answer from what it retrieves, citing sources inline. The default search experience is served by Sonar, Perplexity’s in-house model family (publicly documented as built on Llama). Which exact Sonar variant serves a given query is not user-visible.
Paid subscribers can select other models — including frontier models from other labs — whose answers and citation behavior differ from the default. Discoverably tracks the default that free and unswitched users get, and follows it as Perplexity changes it.
Model history
Every family-level change to the model behind Perplexity, newest first, each linked to its primary source.
Perplexity ships the new in-house Sonar model (built on Llama 3.3 70B) as the default for its search experience.
Perplexity ↗ (opens in a new tab)Perplexity ships the new in-house Sonar model (built on Llama 3.3 70B) as the default for its search experience.
Perplexity ↗ (opens in a new tab)
What decides whether Perplexity names your brand
The purest retrieval-first engine — it searches the live web on essentially every query and cites what it used, so there is no meaningful parametric regime.
How answers form & what drives brand mentions
Retrieval-first. VENDOR-DOCUMENTED Perplexity searches the web in real time, identifies sources, synthesizes, and attaches numbered citations. All leverage concentrates into one question: does your content get retrieved and selected for citation?
The index & crawlers. VENDOR-DOCUMENTED PerplexityBot indexes content; Perplexity-User fetches on a live user’s behalf; both are independently robots-controllable (~24h propagation) and Perplexity advises WAF whitelisting. Sites disallowing PerplexityBot won’t have full text indexed (domain/headline/summary may remain); crawled content is not used to train foundation models; Perplexity also partners with third-party search providers.
crawler docs ↗ (opens in a new tab)robots.txt help ↗ (opens in a new tab)
Selection. Partly documented, partly inference Perplexity describes ranking for helpfulness/trust/freshness rather than click likelihood, but not in a single canonical ranking doc. OUR INFERENCE (RAG two-step): a page must both rank in Perplexity’s index for the query and contain an extractable passage that supports a sentence of the answer.
Citation data. INDEPENDENT STUDY Perplexity is the most community-weighted engine measured — Semrush’s Reddit study (248k cited Reddit URLs across 217k queries) found Reddit the top-cited domain on Perplexity, Q&A threads supplying over half of cited Reddit content. Perplexity’s own materials emphasize freshness, but we found no rigorous public quantification of its magnitude, so we treat freshness as directional only.
Factor weights
Weight and confidence are our editorial estimate of each factor’s influence, and of the evidence for its direction — not a vendor’s ranking weight. No engine publishes a brand-selection formula.
| Factor | Weight | Confidence | Basis |
|---|---|---|---|
| Crawlability by PerplexityBot + WAF allowance (index-inclusion gate) | High (binary gate) | High | VENDOR-DOCUMENTED |
| Ranking in Perplexity’s own index (helpfulness/trust/relevance) | High | Med | Partly vendor-described; specifics undisclosed; weighting OUR INFERENCE |
| Passage extractability (answer-first, one claim per sentence, quotable facts) | High | Med | OUR INFERENCE; KDD-2024 GEO measured its largest gains on Perplexity |
| Presence in community/UGC, especially Reddit Q&A | High | High | INDEPENDENT STUDY (Semrush 2025) |
| Content freshness | High (time-sensitive) | Med | Vendor-described emphasis; magnitude not rigorously quantified |
| Domain-level trust/authority (internal scoring) | Med | Med | Vendor-described concept; scoring undisclosed |
| Google/Bing organic rankings | Low-Med (indirect) | Med | INDEPENDENT STUDY (low top-10 overlap); third-party partners make some coupling plausible |
| Generic schema markup | Low | Low-Med | OUR INFERENCE; no vendor doc of schema in ranking |
What you can do (ranked)
- Verify PerplexityBot + Perplexity-User access end to endengine-specificVENDOR-DOCUMENTED
robots.txt, WAF whitelisting per Perplexity’s guidance, and server-log confirmation; misconfigured bot mitigation silently zeroes citation potential.
- Create the strongest evidence page per high-value questioncross-engineOUR INFERENCE
Retrieval-first architecture makes a retrievable answer-bearing page a prerequisite for dependable citation.
- Earn authentic Reddit / category Q&A presenceengine-specific in intensityINDEPENDENT STUDY
The highest measured community-citation concentration of the six; substantive, well-received answers are the pattern its retrieval selects. Astroturfing violates platform rules and is filtered.
- Lead every page with the answercross-engine · strongest hereINDEPENDENT STUDY
The KDD-2024 GEO benchmark found adding quotations, statistics, and citations improved generative-engine visibility ~28–41% (quotations +41%, statistics +32%, citations +30%), with the strongest tactics validated on Perplexity in the real world.
- Update time-sensitive pages without URL churncross-engineOUR INFERENCE
Stable canonical URL, effective date and changed facts in crawlable text.
- Monitor by citation, not rankengine-specificOUR INFERENCE
Perplexity has no stable SERP; measurement is mention/citation rate over repeated question samples.
Grounding, citation & locality
VENDOR-DOCUMENTED Every answer includes numbered citations linking sources — the densest, most auditable of the six. OUR INFERENCE: visible citations are a selected subset, not the full candidate set or retrieval rank. Locality: approximate location from IP; API city/region controls should not be assumed to describe the consumer UI.
Sources
- Perplexity — how does Perplexity work? (2026-05-01) ↗ (opens in a new tab)
- Perplexity — crawlers ↗ (opens in a new tab)
- Perplexity — robots.txt behavior ↗ (opens in a new tab)
- Perplexity — Search API ↗ (opens in a new tab)
- Perplexity — privacy notice ↗ (opens in a new tab)
- Semrush — Reddit AI search study (2025-11) ↗ (opens in a new tab)
- Aggarwal et al. — GEO, KDD 2024 ↗ (opens in a new tab)
- Fahmy et al. — Data & Policy (2026-04-28) ↗ (opens in a new tab)