Open-source alternative to Perplexity: search over your own documents and RAG

Perplexity is valued for answers with a source link, but what a business usually needs is that same answer over its own documents: policies, contracts, the support knowledge base. That is assembled from open models: embeddings find the relevant chunks, a reranker orders them by real relevance, and a language model writes the answer. It all runs on your own server, documents are never indexed outside, queries are unlimited, and retrieval can be tuned to your terminology. The catch is that this is not a finished product: a vector store, document parsing, index refresh and a UI are a development project. And the model can still sound confident and be wrong, which is why the link to the source document is always shown.

Updated 22 Sep 2026Find a model in 4 questions

What to use instead

Search and RAGRU2024–2026

FRIDA / Giga-Embeddings

Sber (SberDevices) · Russia

Sber embeddings built for Russian: according to the developers, among the best on Russian-language search benchmarks. FRIDA is compact, Giga-Embeddings is more powerful.

  • Search across Russian-language documents
  • RAG for chatbots in Russian
  • Classifying requests and reviews
Sizes
480M – 10B-A1.8B
Hardware
from: Laptop
Commercial use allowedDetails
Search and RAGRUOllamaNot maintained2024

BGE-M3

BAAI · China

A model for meaning-based search in about a hundred languages. The core of RAG: the bot finds the right part of a document before answering.

  • Search across a document base
  • RAG for a chatbot
  • Finding similar requests and duplicates
Sizes
568M
Hardware
from: Laptop
Commercial use allowedDetails
Search and RAGRUOllama2025–2026

Qwen3 Embedding / Reranker

Alibaba (Qwen) · China

Embeddings and rerankers based on Qwen3, among the best open ones for multilingual search, including Russian. VL versions search images, screenshots and video.

  • Knowledge base search for RAG
  • Reranking results before answering
  • Search across scans, slides and screenshots
Sizes
0.6B – 8B
Hardware
from: Laptop
Commercial use allowedDetails
Search and RAGRUNot maintained2022–2024

E5 / multilingual-e5

Microsoft · USA

Proven models for semantic search. The multilingual versions work well with Russian and are still a reliable base for RAG.

  • Search across a knowledge base and documents
  • Finding answers for a chatbot (RAG)
  • Finding similar requests and duplicates
Sizes
33M – 7B
Hardware
from: Laptop
Commercial use allowedDetails
RerankersGGUFNot maintained2023–2024

BGE Reranker

BAAI (Beijing Academy of Artificial Intelligence) · China

Rerankers: they take passages found by search and reorder them by how well they actually match the question. v2-m3 is multilingual and lightweight, often paired with bge-m3.

  • Refining search results before a chatbot answers
  • Sorting knowledge base search results
  • Selecting the most relevant clauses of contracts and policies
Sizes
278M – 9B
Hardware
from: Laptop
Commercial use allowedDetails

All five are listed as commercially usable (MIT and Apache 2.0); only some BGE Reranker variants fall under the Gemma license. The language model that writes the final answer is chosen separately and its license checked the same way.

Other alternatives

Need a model for your task?

An open model can run on your own server: data stays in-house, there is no per-request fee, and the model can be fine-tuned on your documents.

  1. SelectThe model and size for your task and hardware budget
  2. DeployOn your server or in a closed network, with an API
  3. Fine-tuneOn your data, or connect a knowledge base
  4. IntegrateInto your CRM, ERP, bot, website or team chat
Discuss deployment