Claude Sonnet 4.5 vs Gemini 4 Argon
Anthropic · US | Google · US · Updated June 2026
Quick verdict
Pick Claude Sonnet 4.5 for agentic coding — 77.2% on swe-bench verified, the best score any model had posted at its launch or computer use and gui automation (61.4% osworld at launch). Pick Gemini 4 Argon for 1,048,576-token unified context shared by input, thinking and output, with 'long decode' for very long responses or google-reported deepswe v1.1 of 77.9% and lvbench long-video understanding of 91.7%. On a tight budget at scale, Gemini 4 Argon is the value pick.
Claude Sonnet 4.5 (Anthropic) and Gemini 4 Argon (Google) are two of the models people most often weigh against each other in 2026. Claude Sonnet 4.5 is september 2025's coding state of the art at $3/$15 — still supported, but 200K-capped and twice superseded. Gemini 4 Argon is google's Gemini 4 Argon, broadly available October 13, 2026 - a 1M-context model at $2/$10 introductory pricing (doubling December 1). They diverge most on price and context window — each quantified below from the models' real specs.
Key differences at a glance
- ▸Price: Gemini 4 Argon is about 1.5× cheaper on input ($2/$10 per 1M tokens vs $3/$15 per 1M tokens) — modest, but it adds up at steady volume.
- ▸Context window: Gemini 4 Argon holds 5.2× more — 1M tokens (~1,573 pages) vs 200K (~300 pages). But effective recall usually fades long before the advertised ceiling, so the bigger number only helps if the model reasons over it.
- ▸Recency: Gemini 4 Argon is the newer model by about 13 months (released October 13, 2026), usually meaning fresher training data and capabilities.
Side-by-side specs
| Spec | Claude Sonnet 4.5 | Gemini 4 Argon |
|---|---|---|
| Provider | Anthropic (US) | Google (US) |
| Released | September 29, 2025 | October 13, 2026 |
| Context window | 200K (~300 pages) | 1M tokens (~1,573 pages) |
| Price (in/out) | $3/$15 per 1M tokens | $2/$10 per 1M tokens |
| Open weight? | No — API only | No — API only |
| Modalities | text, image, code | text, image, audio, video, code |
| SWE-Bench Verified | 77.2% | Not published |
| MRCR v2 @ 1M | Not published | Not published |
Who wins what
Agentic coding — 77.2% on SWE-Bench Verified, the best score any model had posted at its launch
Claude Sonnet 4.5
Claude Sonnet 4.5 lists agentic coding — 77.2% on SWE-Bench Verified, the best score any model had posted at its launch among its strengths; Gemini 4 Argon does not.
Computer use and GUI automation (61.4% OSWorld at launch)
Claude Sonnet 4.5
Claude Sonnet 4.5 lists computer use and GUI automation (61.4% OSWorld at launch) among its strengths; Gemini 4 Argon does not.
Long-horizon autonomy — Anthropic reported 30+ hours of sustained focus on multi-step tasks
Claude Sonnet 4.5
Claude Sonnet 4.5 lists long-horizon autonomy — Anthropic reported 30+ hours of sustained focus on multi-step tasks among its strengths; Gemini 4 Argon does not.
1,048,576-token unified context shared by input, thinking and output, with 'long decode' for very long responses
Gemini 4 Argon
Its 1M tokens window holds about 5.2× more than Claude Sonnet 4.5's 200K in a single prompt.
Google-reported DeepSWE v1.1 of 77.9% and LVBench long-video understanding of 91.7%
Gemini 4 Argon
Google's Gemini 4 Argon, broadly available October 13, 2026 - a 1M-context model at $2/$10 introductory pricing (doubling December 1) — and it runs cheaper at $2/$10 per 1M tokens.
Artificial Analysis Intelligence Index of 53 at high effort (AI Weekly)
Gemini 4 Argon
Claude Sonnet 4.5 is comparatively weak here — missing the modern API surface: no adaptive thinking, no effort control, and half the max output of newer Sonnets
Lowest cost at scale
Gemini 4 Argon
At $2/$10 per 1M tokens, it is the cheaper of the two — the gap dominates the bill on high-volume workloads.
Largest single-prompt input
Gemini 4 Argon
Its 1M tokens window is about 5.2× larger than Claude Sonnet 4.5's 200K, fitting roughly 1,573 pages in one prompt.
Which should you pick?
A cost-sensitive startup shipping high volume
→ Gemini 4 Argon
At $2/$10 per 1M tokens it undercuts Claude Sonnet 4.5, and on millions of tokens that margin decides the monthly bill.
Someone analysing very long documents or codebases
→ Gemini 4 Argon
Larger 1M tokens window fits more in one prompt.
Anyone whose priority is agentic coding — 77.2% on swe-bench verified, the best score any model had posted at its launch
→ Claude Sonnet 4.5
It is specifically built for that.
Anyone whose priority is 1,048,576-token unified context shared by input, thinking and output, with 'long decode' for very long responses
→ Gemini 4 Argon
That is its strongest area.
Claude Sonnet 4.5: where it fits
September 2025's coding state of the art at $3/$15 — still supported, but 200K-capped and twice superseded. Released September 29, 2025 by Anthropic, it is built for agentic coding — 77.2% on SWE-Bench Verified, the best score any model had posted at its launch, computer use and GUI automation (61.4% OSWorld at launch), long-horizon autonomy — Anthropic reported 30+ hours of sustained focus on multi-step tasks, and tracking its own remaining token budget natively, which few models do.
Its trade-offs are real: superseded twice — Sonnet 4.6 and Sonnet 5 match or beat it at the same or lower price, capped at 200K since Anthropic retired its 1M beta in April 2026, while its successors ship 1M as standard, and missing the modern API surface: no adaptive thinking, no effort control, and half the max output of newer Sonnets. At $3 in / $15 out per million tokens, it sits in the mid price band.
Gemini 4 Argon: where it fits
Google's Gemini 4 Argon, broadly available October 13, 2026 - a 1M-context model at $2/$10 introductory pricing (doubling December 1). Released October 13, 2026 by Google, it is built for 1,048,576-token unified context shared by input, thinking and output, with 'long decode' for very long responses, google-reported DeepSWE v1.1 of 77.9% and LVBench long-video understanding of 91.7%, and artificial Analysis Intelligence Index of 53 at high effort (AI Weekly).
Its trade-offs: introductory $2/$10 pricing ends November 30; from December 1 it doubles to $4/$20, verbose: about 62K output tokens per Artificial Analysis task, so cost per task is high, and announced September 30 for trusted cyber defenders only; broad paid-tier availability followed October 13 (not on the free tier). At $2 in / $10 out per million tokens, it sits in the mid price band.
The bottom line for this matchup
Claude Sonnet 4.5 and Gemini 4 Argon overlap enough that the right pick depends on your specific job. Gemini 4 Argon costs less per token; Gemini 4 Argon holds the larger context; and each leads in its own area — Claude Sonnet 4.5 for agentic coding — 77.2% on swe-bench verified, the best score any model had posted at its launch, Gemini 4 Argon for 1,048,576-token unified context shared by input, thinking and output, with 'long decode' for very long responses. Rather than crowning one, run the same hard task through both once and let the results decide.
Want both Claude Sonnet 4.5 and Gemini 4 Argon without two subscriptions? LumiChats gives you these plus 40+ models under one ₹69/day pass (about $1/day) — draft with one, cross-check with the other.
See pricingFrequently asked questions
Is Claude Sonnet 4.5 or Gemini 4 Argon better for coding?
Public SWE-Bench figures are not available for Gemini 4 Argon, so the honest test is your own repository — run an identical real bug through both. By design, Claude Sonnet 4.5 leans toward agentic coding — 77.2% on swe-bench verified, the best score any model had posted at its launch while Gemini 4 Argon leans toward 1,048,576-token unified context shared by input, thinking and output, with 'long decode' for very long responses, and that positioning usually predicts which feels better on your codebase.
Which is cheaper, Claude Sonnet 4.5 or Gemini 4 Argon?
Gemini 4 Argon is cheaper — $3/$15 per 1M tokens vs $2/$10 per 1M tokens, roughly 1.5× apart on input.
Which has the bigger context window?
Gemini 4 Argon — 1M tokens vs 200K, about 5.2× larger. Useful only if the model actually reasons over the full window, which not all do.
Can I use both Claude Sonnet 4.5 and Gemini 4 Argon together?
Yes — a multi-model platform like LumiChats gives you Claude Sonnet 4.5, Gemini 4 Argon and 40+ others under one ₹69/day pass (about $1/day), so you can draft with one and cross-check with the other instead of buying two subscriptions.
Which is newer, Claude Sonnet 4.5 or Gemini 4 Argon?
Gemini 4 Argon — released October 13, 2026, about 13 months after Claude Sonnet 4.5.
Related comparisons
Specifications and benchmarks reflect publicly reported figures as of June 2026 and may change as providers release updates. Always verify on your own workload.