Completely open-source and free (Apache 2.0), with no subscription model; uses local models (such as Ollama) at zero cost; API call fees depend on the chosen LLM provider
Cheapest paid plan: API pay-as-you-go (usage-based)
The cloud platform has no ongoing free plan; Pro has a 7-day free trial (read directly from strix.ai/pricing in a browser on 2026-09-24). What is truly free is the open-source CLI: the official docs say it installs with curl or pipx, requires Docker running and an LLM API key from any supported provider (OpenAI, Anthropic, Google, etc.) — the software is free and you pay the model provider for inference. It can scan local code, a GitHub repo or a live website, and the open-source version has no run limits or watermark (read directly in a browser on 2026-09-09).
Cheapest paid plan: US$29 / user / mo (5 user ≈ US$145/mo)
Aider itself is free, the cost of LLM API is determined by the provider chosen by the user, usually ranging from US$10-30 per month (light usage) to US$50-200+ per month (heavy usage)
Strix
Plan
Price
What you get
Pro
US$29 / user / mo (5 user ≈ US$145/mo)
Platform subscription: US$29 per seat per month, with pentests billed separately (pay per test). Includes API and web app pentesting, PR security reviews, one-click autofix, attack surface monitoring, scheduled pentesting, and Jira/Linear/Slack integrations; 7-day free trial. Read directly from strix.ai/pricing in a browser on 2026-09-24.
Rightsized Pentest
US$60 (One-time purchase)
Official price US$60–300 per test (depends on target size; formerly called One-time Pentest, previously listed from 59 dollars): self-serve testing of apps, APIs and repos, whitebox and authenticated testing, validated findings with proof-of-exploit, autofix, OWASP Top 10 coverage, and a free re-test after fixes. ⚠️ This price appears only on the official site (Pentest tab); third-party intruder.io says a standalone pentest starts from US$1,000, which does not match the official site, so we follow the official site. Read directly in a browser on 2026-09-24.
Full Audit
US$2000 (One-time purchase)
Official price from US$2,000 per audit (one-time deep audit): everything in Rightsized Pentest, plus business logic and attack chain testing, a formal SOC 2 / ISO 27001 report, custom scope and test accounts, review by CREST-certified pentesters, and same-day results.
Enterprise
Official quote (upon inquiry)
Custom (Get a quote): Periodic audits across all environments, covering internal apps and infrastructure, with customizable scope and SLA, SSO, audit logs, and a dedicated success manager.
Which one should you pick?
If you want to try before paying, aider has a free plan and Strix does not — start with aider.
aider has no public paid plan; Strix starts at about US$29 / user / mo.
FAQ
Is there a free version of aider?
Yes. Completely open-source and free (Apache 2.0), with no subscription model; uses local models (such as Ollama) at zero cost; API call fees depend on the chosen LLM provider
How much does aider cost?
The cheapest is the plan from aider named API cost (self-selected provider), at about Official quote (upon inquiry).
Does aider support Chinese?
aider only partially supports Chinese.
Is there a free version of Strix?
No public free plan — a subscription is required.
How much does Strix cost?
The cheapest is the plan from Strix named Pro, at about US$29 / user / mo.
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