Synthetic

What it does

Synthetic provides hosted access to open-source language models through its app and API. People can use the app for model access, or connect compatible clients and coding-agent tools. The API accepts OpenAI-compatible and Anthropic-compatible requests, with endpoints for chat and text completions, embeddings, message handling, token counting, quota checks, and web search.

The service is aimed at people using open-source models, including researchers, engineers, and coding-agent users. The API requires a Synthetic account and API key; the documentation says users must log in to see their key. The pricing page lists Go, Standard, and Big subscriptions, weekly credits at discounted model rates, and extra usage at API pricing. The included quota is model-dependent, and the documentation do not state exact API rates or clarify the subscription billing cadence.

Model availability, rate limits and beta features depend on the selected tier. Weekly credits regenerate and different models consume them at different rates. Extra API usage is charged separately. Big includes beta Fast mode, which consumes rate-limit allowance faster, and beta Infinite mode for slower background requests on specified supported models; it is not unrestricted access to every model.

What it can do

• Hosted access to supported open-source language models
• OpenAI-compatible API for chat and text completions
• Anthropic-compatible API for messages and token counting
• Text embeddings endpoint
• Web search API
• App and API subscription usage with weekly credit quotas

Works with

• OpenAI-compatible tools and clients
• Anthropic-compatible clients
• Roo
• Cline
• Octofriend

Before you choose

• API rate limits vary by subscription tier; extra usage is available at API pricing, but exact rates are not included in the pricing documentation.
• Pricing lists weekly credits and model-dependent token estimates; it does not establish an exact API billing unit or subscription billing cadence.
• Infinite mode is marked beta, runs more slowly, and is currently available only for DeepSeek V 4.1 Flash.

Listed under

• Coding
• MCP and agent tools
• Chat interface
• Coding agents
• Developers
• Flat subscription
• LLM API
• Open-source LLMs

Get started

The homepage links to account registration.

1. Create a Synthetic account from the sign-up page.
2. For API use, log in to obtain an API key; the docs show requests authenticated with a bearer token.
3. Choose an available model and use the app or configure an OpenAI-compatible or Anthropic-compatible client.

The page displays monthly amounts but does not say whether billed monthly or annually. Weekly credits regenerate and apply at discounted model rates; additional usage is charged at API pricing. Exact extra-usage rates and units are not established in vendor documentation.

Source: synthetic.new/pricing, checked 1 Nov 2026. Prices can change; check before you buy.

Sources for this overview

Product pages, documentation, and pricing checked 1 Nov 2026. Each source supports part of the overview; availability and prices can change.

• Synthetic | Run LLMs, privately ↗synthetic.new
• API Overview | Synthetic ↗dev.synthetic.new
• Pricing | Synthetic ↗synthetic.new
• A flat monthly subscription to open-source LLMs | Synthetic ↗synthetic.new

Company website

synthetic.new: product, pricing and policy pages

YC directory mirror

Batch and company name

Human review

Checked by a person

knowledge_base

manual_review

Last checked 1 Nov 2026. Every field keeps its source and date; unknown means we couldn’t confirm it.