Claude Opus 5.5 vs GPT-6 Sol Cost Calculator

This calculator uses the list prices published by Anthropic and OpenAI as of 23 September 2026. For what the models can actually do, see the full breakdowns of Claude Opus 5.5 and GPT-6 Sol and Luna, and the head-to-head comparison.

1. The calculator

The calculator runs entirely in your browser and sends nothing anywhere. If JavaScript is off, the five worked workloads in section 4 show the same results for the preset inputs.

2. The price sheet behind it

USD per million tokens, from the Claude Platform pricing page and OpenAI's model pages. Confirmed Both companies discount Batch requests by 50%. Both also offer a fast mode at a premium: $8 / $40 for Opus 5.5 on the Claude API, and 2× standard rates for OpenAI models. Confirmed

3. How the calculator works

For each model, the cost of one request is:

cost = fresh_input × input_price
     + cached_input × cache_read_price
     + cache_writes × cache_write_price
     + output × output_price × output_multiplier

OpenAI models, when fresh + cached + writes > 272,000 tokens:
     input, cache read and cache write prices × 2, output price × 1.5

Batch ticked: total × 0.5

Assumptions to be aware of: Assumptions

• Output includes reasoning. Both companies bill thinking or reasoning tokens as output. If you estimate output from the visible answer alone, you'll undercount, often by a lot at high effort and above.
• The same token counts are used for every model by default. In reality, the two companies' tokenizers split text differently, and the models think for different lengths. The output multipliers in the Advanced section let you correct for this.
• Batch is applied on top of caching for every model. Anthropic documents that the two discounts stack. For OpenAI, check how your specific setup is billed.
• Cache writes use the 5-minute rate on Claude models. One-hour caching costs more ($8 per million on Opus 5.5).
• Not included: web search ($10 per 1,000 calls on both), other tool fees, data-residency premiums (+10%) and fast mode.

4. Five workloads, worked out

These are the calculator's five presets, at list prices with no batch discount. Calculation

Coding agent

1,000 requests, each with 10,000 fresh input tokens, 50,000 cached input tokens and 3,000 output tokens.

Output-heavy drafting

1,000 requests, each with 20,000 input tokens and 20,000 output tokens (reports, long code files, content drafts).

One 400K-token document

A single request with a 400,000-token document and a 5,000-token answer.

Bulk classification

10,000 requests, each with 300 input tokens and 50 output tokens (intent tagging, sentiment, routing).

Support chat

10,000 conversations, each with 2,000 fresh input tokens, 8,000 cached tokens (policies and product info) and 500 output tokens.

5. Cost per token vs cost per finished task

The calculator compares models on identical token counts. Real models don't use identical token counts. The one independent measurement that ran both through the same ten evaluations is Artificial Analysis's Intelligence Index, at max effort: Observed

So at max effort, Opus 5.5 costs about 3.8× as much per task, not 2×, because it also thinks for about 3.8× as many tokens. To model that, set the Claude output multiplier to about 3.8 in the Advanced section. At default medium effort the ratio is likely lower, since Anthropic's early-access partners reported Opus 5.5 using 20–60% fewer tokens than Opus 5, but no independent medium-effort figure has been published yet. Analysis

What decides it in the end is cost per successful task: a cheaper model that fails more often and needs a human to fix the result can cost more overall. That method is worked through in what AI models actually cost per task.

6. Five ways to cut the bill, on either model

1. Cache everything you resend. On Opus 5.5 and Sol alike, cached input costs $0.20 per million, 5% of Opus 5.5's input price and 10% of Sol's. For agents that resend a big system prompt every turn, this is the biggest single lever.
2. Batch anything that can wait. Overnight classification, bulk rewrites and evaluation runs get 50% off on both platforms.
3. Set effort deliberately. Opus 5.5 and Sol both default to medium. Raise it only for tasks where you've measured a quality gain; max can multiply output tokens several times over.
4. Keep OpenAI prompts under 272K tokens, or send long ones to Claude. Above the threshold, Sol's price advantage disappears and Astra's cost doubles.
5. Route by task. Luna for repetitive jobs with clear answers, Sol for routine agent turns and drafts, Opus 5.5 for long, high-stakes or judgement-heavy work. The comparison article sets out a four-tier routing plan.

7. Frequently asked questions

Work with me

AI workflows that are cheap to run and easy to trust

I'm Jayant Solanki, an SEO, GEO and automation strategist working with eCommerce, local-service and global brands. I build AI-assisted SEO and content workflows that use the cheapest model that does each job well, and I measure them so the savings are real.

An automation engagement typically covers:

• Mapping current AI usage by task, volume and cost
• Benchmarking each task on the models that could do it
• Routing, caching and batch processing set up where they pay off
• Quality checks so cheaper never quietly means worse
• A monthly cost and quality report

Book a technical review → See automations

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Sources

• Claude Platform Docs, Pricing (model, cache, batch, fast mode and long-context pricing)
• Claude Platform Docs, Claude Opus 5.5 model page
• OpenAI API docs, GPT-6 Sol and GPT-6 Luna model pages (prices, cache rates, 272K rule)
• OpenAI API docs, GPT-6 Astra model page
• Artificial Analysis, Claude Opus 5.5 analysis; OfficeChai, GPT-6 Sol on the Artificial Analysis Intelligence Index
• The Decoder, Claude Opus 5.5 matches Fable 5.1 at 40 percent lower cost (output tokens per task)

Jayant Solanki

AI-Ready SEO, GEO & AIO strategist based in Indore, India, working with eCommerce, local-service and global brands across India, the UAE and the US. The calculator's prices will be updated when Anthropic or OpenAI change them, and when Sonnet 5.5 and Haiku 5.5 launch.

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