API cost decision in 10 seconds

Claude Opus 4.6 (Fast) vs 🔥GPT-5.4

Pick GPT-5.4 when budget and context both matter.

Pricing data updated:  Prices normalized to USD per 1M tokens Sample workload: 1M input + 500K output

Budget verdict

Pick GPT-5.4 when budget and context both matter.

On the standard 1M input plus 500K output workload, GPT-5.4 is estimated at $10 vs $105 for Claude Opus 4.6 (Fast), saving $95 (90.5% lower).

Cost-first pickGPT-5.4
Context-first pickGPT-5.4
Sample savings$9590.5%
10x traffic gap$950

GPT-5.4 is cheaper on the standard workload and also has the larger context window. At 10x that traffic, the same price gap is about $950. Use the calculator below to replace the sample workload with your own token volume.

Cost sensitivity

Workload Sensitivity

Same prices, different token mixes.

GPT-5.4 stays cheaper across input-heavy, balanced, and output-heavy sample workloads.

Workload shapeToken mixBetter pickClaude Opus 4.6 (Fast)GPT-5.4
Input-heavy / RAG 5M input + 500K output GPT-5.4 $225 $20
Balanced workload 1M input + 1M output GPT-5.4 $180 $17.5
Output-heavy chatbot 1M input + 5M output GPT-5.4 $780 $77.5
Cheaper inputGPT-5.4$30 vs $2.5 / 1M
Cheaper outputGPT-5.4$150 vs $15 / 1M
Larger contextGPT-5.41M vs 1.05M
Sample workloadGPT-5.4$105 vs $10

Estimate your workload cost

Your Workload Cost

Prices are normalized to USD per 1M tokens.
Claude Opus 4.6 (Fast)Calculating…Estimated API cost
GPT-5.4Calculating…Estimated API cost
Cheaper for this workloadCalculating…Difference: calculating…

This estimate uses normalized public API pricing per 1M tokens. It is a planning aid, not a billing quote. Verify provider pricing, limits, and terms before production use.

Quick Decision

Verdict

GPT-5.4 has the lower input price, GPT-5.4 has the lower output price, and GPT-5.4 offers the larger context window.

For a 1M input token plus 500K output token workload, the estimated API cost is $105 for Claude Opus 4.6 (Fast) and $10 for GPT-5.4.

Best Fit

Choose Claude Opus 4.6 (Fast) when its provider, model quality, latency, or availability is more important than the numeric price/context winner.

Choose GPT-5.4 when you care most about lower input-token price, lower output-token price, and larger context window.

Head-to-Head Specs
FeatureClaude Opus 4.6 (Fast)
(Anthropic)		🔥GPT-5.4
(OpenAI)
Input Price
prompt tokens per 1M		$30$2.5
Completion Price
per 1M tokens		$150$15
Sample Workload Cost
1M input + 500K output		$105$10
Context Window1M1.05M
Release Date2026-04-072026-03-05
Popularity#19
Claude Opus 4.6 (Fast)

Fast-mode variant of [Opus 4.6](/anthropic/claude-opus-4.6) - identical capabilities with higher output speed at premium 6x pricing. Learn more in Anthropic's docs: https://platform.claude.com/docs/en/build-with-claude/fast-mode

GPT-5.4

GPT-5.4 is OpenAI’s latest frontier model, unifying the Codex and GPT lines into a single system. It features a 1M+ token context window (922K input, 128K output) with support for...

Use-Case Decision Matrix

Use caseBetter pickWhy
Budget-constrained productionGPT-5.4On the standard 1M input plus 500K output workload, GPT-5.4 is estimated at $10 vs $105 for Claude Opus 4.6 (Fast), saving $95 (90.5% lower).
High-volume input processingGPT-5.4Lower prompt-token price matters most when prompts or retrieved passages dominate the bill.
Long responses and chatbotsGPT-5.4Lower output-token price matters most when assistants generate many completion tokens.
RAG or long-document workGPT-5.4A larger context window leaves more room for retrieved passages and source files.