# Gemini 4 Argon vs Claude Opus 5.5: API price before and after Dec 1

Canonical: https://theagenticweekly.com/compare/gemini-4-argon-vs-claude-opus-5-5 · Last verified: 2026-10-27 · Published: 2026-10-27 · Author: Agentic Weekly (operated independently from Texas, US) · Evidence: Evidence: Reported. Prices and specs are read from Google's and Anthropic's pages listed under Sources on 2026-10-27 (America/Chicago). Benchmark rows are third-party mirrors with different harnesses. We have not run either model for this page.

> Gemini 4 Argon costs $2 per million input tokens and $10 per million output tokens through November 30, 2026, half of Claude Opus 5.5's $4 and $20. From December 1 Argon moves to $4 and $20, the same list price as Opus 5.5. Token counts per task differ by model. Last verified 2026-10-27 (America/Chicago).

## Gemini 4 Argon vs Claude Opus 5.5 at a glance

Table: Gemini 4 Argon and Claude Opus 5.5, read from Google's and Anthropic's pages on 2026-10-27

|  | Gemini 4 Argon | Claude Opus 5.5 |
|---|---|---|
| Released | 2026-10-13 (Google launch post) | 2026-09-22 (Anthropic) |
| API model id | `gemini-4-argon` | `claude-opus-5-5` |
| Input price, per 1M tokens | $2.00 through 2026-11-30; $4.00 from 2026-12-01 | $4.00 |
| Output price, per 1M tokens | $10.00 through 2026-11-30; $20.00 from 2026-12-01 (includes thinking tokens) | $20.00 |
| Cached input, per 1M tokens | $0.10, then $0.20 from 2026-12-01 (implicit caching only) | $0.20 (cache read) |
| Batch input / output, per 1M tokens | $1.00 / $5.00, then $2.00 / $10.00 from 2026-12-01 | $2.00 / $10.00 |
| Context window | 1,048,576 tokens (input and output combined) | 1M tokens |
| Max output | 65,536 (default); up to 1,048,576 with long decode | 128K tokens |
| Input types | Text, image, video, audio, PDF | Text, image |
| Output | Text | Text |
| Free tier | Not available on the Gemini API Free tier | Not covered on the pages we read; see [Opus 5.5: free or paid?](https://theagenticweekly.com/guides/claude-opus-5-5-free-or-paid) |

Sources: [Google pricing](https://ai.google.dev/gemini-api/docs/pricing), [Argon model page](https://ai.google.dev/gemini-api/docs/models/gemini-4-argon), [Anthropic models overview](https://platform.claude.com/docs/en/about-claude/models/overview), [Anthropic pricing](https://platform.claude.com/docs/en/about-claude/pricing). Full facts: [Gemini 4 Argon](https://theagenticweekly.com/models/gemini-4-argon) and [Claude Opus 5.5](https://theagenticweekly.com/models/claude-opus-5-5).

## Cost of one example task, before and after Dec 1

Illustration only, our arithmetic from list prices: one task with 200,000 uncached input tokens and 20,000 output tokens, with the same counts for both models. Real counts differ by model: Anthropic says Claude 4.7 and later models use a tokenizer that produces about 30% more tokens for the same text than earlier Claude models, and Google does not publish a like-for-like figure. Batch and caching change the bill.

Table: Illustrative cost of one task (200K input + 20K output tokens) at standard list prices, our arithmetic, 2026-10-27

| Model and period | List price per 1M tokens | Cost per task | Cost per 100 tasks |
|---|---|---|---|
| Gemini 4 Argon, through 2026-11-30 | $2.00 in + $10.00 out | $0.60 | $60.00 |
| Gemini 4 Argon, from 2026-12-01 | $4.00 in + $20.00 out | $1.20 | $120.00 |
| Claude Opus 5.5 | $4.00 in + $20.00 out | $1.20 | $120.00 |

At these counts, Argon is half the cost of Opus 5.5 until November 30 and the same cost from December 1. Neither figure is a measured bill. Our pricing guide has the full table: [Gemini 4 Argon API pricing](https://theagenticweekly.com/guides/gemini-4-argon-api-pricing).

## If you buy Argon through Google Cloud

Google's Cloud pricing page for Gemini on its agent platform shows Argon's promotional price as "50% credits back" on net spend through November 30, 2026, not a lower list price. It also says that when a Gemini 4 completion exceeds 32K tokens, users are charged for retrievable token usage even if the request fails on a client or server timeout, effective November 13, 2026. Read that page before budgeting for long completions: [Google Cloud pricing](https://cloud.google.com/gemini-enterprise-agent-platform/generative-ai/pricing). The Gemini API pricing page we cite above does not carry that note.

## Reported benchmark rows, with the harness caveat

Both vendors make claims about their own model: Google says Argon is #1 on the Vals Index, and Anthropic says Opus 5.5 leads in agentic coding and knowledge work. We did not verify either. The only head-to-head rows we found are third-party mirrors of Terminal-Bench 4.0 on BenchLM, and each row uses its own harness and settings, so they are not a controlled comparison.

Table: Terminal-Bench 4.0 rows mirrored by BenchLM, read 2026-10-27; settings differ by row

| Source of the row | Claude Opus 5.5 | Gemini 4 Argon |
|---|---|---|
| Vals AI (Vals-hosted table) | 65.15% | 57.58% (high reasoning) |
| Artificial Analysis (its own harness) | 59.6% | 57.1% |

Opus 5.5 scores higher than Argon in both tables, by 7.57 points and 2.5 points (our subtraction), but the gap changes with the harness, which is the point of the [Terminal-Bench 4.0 explainer](https://theagenticweekly.com/guides/terminal-bench-4-explained). BenchLM's official-leaderboard table, which lists Opus 5.5 at 64.85%, did not include an Argon row when we read it. Source: [BenchLM Terminal-Bench 4.0](https://benchlm.ai/benchmarks/terminal-bench-4).

## Which to pick when

- **Budget before Dec 1 and the work can finish by Nov 30:** Argon's list price is half of Opus 5.5's until then. Google gives no way to lock the introductory price past Nov 30.
- **Budget for December onward:** the two have the same list price, so choose on fit, token use per task and tooling, not on the sticker.
- **Video, audio or PDF input:** Argon accepts them per Google's model page; Opus 5.5's overview lists text and image input.
- **Very long outputs:** Argon lists up to 1,048,576 output tokens with long decode; Opus 5.5 lists 128K max output.
- **Claude-specific tools or Anthropic's platform features:** Opus 5.5 is Anthropic's recommended starting model for most workloads per its models overview.

## What we did not test

We did not call either API or run either model, so we have no measurements of speed, accuracy, token use or cost on a real workload. Every figure is a vendor page or a cited third-party table read on 2026-10-27.

## FAQ

### Is Gemini 4 Argon cheaper than Claude Opus 5.5?

Until November 30, 2026, yes at list price: Argon is $2 input and $10 output per million tokens versus $4 and $20 for Opus 5.5. From December 1, Argon is $4 and $20, so the list prices match. Token use per task can still differ.

### When does the Argon price change?

Google's pricing page says the introductory prices apply through November 30, 2026 and the higher prices start December 1, 2026: $4.00 input and $20.00 output per million tokens on the paid tier at standard rates. Argon is not available on the Free tier.

### Which model scores higher on Terminal-Bench 4.0?

Opus 5.5 scores higher than Argon in the two third-party tables we found, by 7.57 and 2.5 points. The rows use different harnesses and settings, so treat them as reported figures, not a controlled head-to-head.

### Does Argon support more input types than Opus 5.5?

Per vendor pages, yes: Google lists text, image, video, audio and PDF input for Argon, while Anthropic's overview says its current models support text and image input with text output.

### Have you tested Gemini 4 Argon or Claude Opus 5.5?

No. This page reports vendor pages and third-party tables as read on 2026-10-27. We have not called either API or measured quality, speed or a real bill, so the cost example is arithmetic on list prices, not a measured cost.

## Sources

- [Google AI for Developers: Gemini API pricing](https://ai.google.dev/gemini-api/docs/pricing) (fetched 2026-10-27)
- [Google AI for Developers: Gemini 4 Argon model page](https://ai.google.dev/gemini-api/docs/models/gemini-4-argon) (fetched 2026-10-27)
- [Google: Introducing Gemini 4 Argon](https://blog.google/innovation-and-ai/models-and-research/gemini-models/introducing-gemini-4-argon/) (fetched 2026-10-27)
- [Google Cloud: Gemini pricing on the agent platform](https://cloud.google.com/gemini-enterprise-agent-platform/generative-ai/pricing) (fetched 2026-10-27)
- [Anthropic: models overview](https://platform.claude.com/docs/en/about-claude/models/overview) (fetched 2026-10-27)
- [Anthropic: pricing](https://platform.claude.com/docs/en/about-claude/pricing) (fetched 2026-10-27)
- [BenchLM: Terminal-Bench 4.0 (mirror of Vals and Artificial Analysis rows)](https://benchlm.ai/benchmarks/terminal-bench-4) (fetched 2026-10-27)

## Related

- [Gemini 4 Argon: facts and sources](https://theagenticweekly.com/models/gemini-4-argon)
- [Claude Opus 5.5: facts and sources](https://theagenticweekly.com/models/claude-opus-5-5)
- [Gemini 4 Argon API pricing](https://theagenticweekly.com/guides/gemini-4-argon-api-pricing)
- [Claude Opus 5.5: free or paid?](https://theagenticweekly.com/guides/claude-opus-5-5-free-or-paid)
- [Claude Opus 5.5 vs Claude Sonnet 5.5](https://theagenticweekly.com/compare/claude-opus-5-5-vs-claude-sonnet-5-5)
- [Terminal-Bench 4.0 explained](https://theagenticweekly.com/guides/terminal-bench-4-explained)
- [AI model release calendar](https://theagenticweekly.com/models/upcoming)

## Changelog

- 2026-10-27: First published from Google's and Anthropic's pricing and model pages and BenchLM's Terminal-Bench 4.0 mirror, read on this date. Nothing was run. Planned: re-read on 2026-12-01.

## How to cite

Agentic Weekly, "Gemini 4 Argon vs Claude Opus 5.5: API price before and after Dec 1", last updated 2026-10-27, https://theagenticweekly.com/compare/gemini-4-argon-vs-claude-opus-5-5