TL;DR — a genuine value-tier fight: Sonnet 5 at $2/$10 (now permanent) vs Gemini 3 Pro at $1.25/$5 — Gemini holds the price edge. Every number below is from our weekly-verified pricing tracker (verified 2026-09-13).
Pricing side by side (per 1M tokens, USD)
| Model | Provider | Input | Output |
|---|---|---|---|
| Claude Sonnet 5 | Anthropic | $2 | $10 |
| Gemini 3 Pro | $1.25 | $5 |
Verified 2026-09-13 against official rate cards — the tracker keeps the change log. Note: Claude Sonnet 5 — introductory $2/$10 made permanent; the planned Sept 1, 2026 rise to $3/$15 was cancelled.
What a real month costs
At a standard workload of 10M input + 2M output tokens/month:
- Claude Sonnet 5: $40.00
- Gemini 3 Pro: $22.50
On this mix, Gemini 3 Pro is the cheaper column (1.8× gap). Your ratio will differ — run your own mix through the LLM cost calculator.
Choose Claude Sonnet 5 if
Anthropic-side strengths (writing quality, instruction following on your evals) justify the gap — and Sonnet's rate no longer carries an expiry that could widen it.
Choose Gemini 3 Pro if
price-per-capability is the metric: Gemini 3 Pro's $5 output is half of Sonnet's, and that gap is now a stable fact rather than a promo artifact.
Routing decision card
- Both compete for the 'default reasoning' rung — this is one of the highest-leverage A/Bs to actually run on your own traffic
- Gemini wins list price; the verdict flips only if your evals show a quality gap on your tasks
- Whichever wins, keep the other as fallback — provider outages are a routing feature, not an edge case
- The router answer: most teams shouldn't hard-pick one — ClawRouters routes each request to whichever side fits it, so the comparison becomes a per-call decision instead of a bet.
Part of the LLM model comparison index. Prices move fast in 2026 — the tracker logs every change with dates.