API cost decision in 10 seconds

GPT-5.1 Chat vs Sonar Pro Search

Pick GPT-5.1 Chat for lower cost; pick Sonar Pro Search only if the larger context window matters more.

Pricing data updated: 2026-05-26T11:08:00Z Prices normalized to USD per 1M tokens Sample workload: 1M input + 500K output

Budget verdict

Pick GPT-5.1 Chat for lower cost; pick Sonar Pro Search only if the larger context window matters more.

On the standard 1M input plus 500K output workload, GPT-5.1 Chat is estimated at $6.25 vs $10.5 for Sonar Pro Search, saving $4.25 (40.5% lower).

Cost-first pickGPT-5.1 Chat

Context-first pickSonar Pro Search

Sample savings$4.2540.5%

10x traffic gap$42.5

Sonar Pro Search has more context, but GPT-5.1 Chat saves $4.25 on the standard workload. At 10x that traffic, the same price gap is about $42.5. Use the calculator below to replace the sample workload with your own token volume.

Cost sensitivity

Workload Sensitivity

Same prices, different token mixes.

GPT-5.1 Chat stays cheaper across input-heavy, balanced, and output-heavy sample workloads.

Workload shape	Token mix	Better pick	GPT-5.1 Chat	Sonar Pro Search
Input-heavy / RAG	5M input + 500K output	GPT-5.1 Chat	$11.25	$22.5
Balanced workload	1M input + 1M output	GPT-5.1 Chat	$11.25	$18
Output-heavy chatbot	1M input + 5M output	GPT-5.1 Chat	$51.25	$78

Cheaper input GPT-5.1 Chat $1.25 vs $3 / 1M

GPT-5.1 Chat is $1.75 cheaper per 1M input tokens (58.3% lower; 2.4x difference).

Cheaper output GPT-5.1 Chat $10 vs $15 / 1M

GPT-5.1 Chat is $5 cheaper per 1M output tokens (33.3% lower; 1.5x difference).

Larger context Sonar Pro Search 128K vs 200K

Sonar Pro Search has 72K more context (1.56x larger).

Sample workload GPT-5.1 Chat $6.25 vs $10.5

GPT-5.1 Chat is $4.25 cheaper on the standard workload (40.5% lower).

Estimate your workload cost

Your Workload Cost

Prices are normalized to USD per 1M tokens.

Monthly input tokens Monthly output tokens

GPT-5.1 Chat Calculating… Estimated API cost

Sonar Pro Search Calculating… Estimated API cost

Cheaper for this workload Calculating… 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-5.1 Chat has the lower input price; GPT-5.1 Chat has the lower output price; Sonar Pro Search offers the larger context window. For the 1M input plus 500K output sample, GPT-5.1 Chat is cheaper for the standard workload.

For a 1M input token plus 500K output token workload, the estimated API cost is $6.25 for GPT-5.1 Chat and $10.5 for Sonar Pro Search.

Best Fit

Choose GPT-5.1 Chat when you care most about lower input-token price, and lower output-token price.

Choose Sonar Pro Search when you care most about larger context window.

Decision Notes

On the standard 1M input plus 500K output workload, GPT-5.1 Chat is estimated at $6.25 vs $10.5 for Sonar Pro Search, saving $4.25 (40.5% lower).
GPT-5.1 Chat is $4.25 cheaper on the standard workload (40.5% lower).
GPT-5.1 Chat is $1.75 cheaper per 1M input tokens (58.3% lower; 2.4x difference).
GPT-5.1 Chat is $5 cheaper per 1M output tokens (33.3% lower; 1.5x difference).
Sonar Pro Search has 72K more context (1.56x larger).

Head-to-Head Specs

Feature	GPT-5.1 Chat (OpenAI)	Sonar Pro Search (Perplexity)
Input Price prompt tokens per 1M	$1.25	$3
Completion Price per 1M tokens	$10	$15
Sample Workload Cost 1M input + 500K output	$6.25	$10.5
Context Window	128K	200K
Release Date	2025-11-13	2025-10-30

Use-Case Decision Matrix

Use case	Better pick	Why
Budget-constrained production	GPT-5.1 Chat	On the standard 1M input plus 500K output workload, GPT-5.1 Chat is estimated at $6.25 vs $10.5 for Sonar Pro Search, saving $4.25 (40.5% lower).
High-volume input processing	GPT-5.1 Chat	Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill.
Long responses and chatbots	GPT-5.1 Chat	Lower output-token price matters most when assistants generate many completion tokens.
RAG or long-document work	Sonar Pro Search	A larger context window leaves more room for retrieved passages, conversation history, or source files.

Related Alternatives

Same-provider lower-cost swaps

gpt-oss-120b (free) can replace GPT-5.1 Chat when lower sample workload cost matters most: $0.
gpt-oss-20b (free) can replace GPT-5.1 Chat when lower sample workload cost matters most: $0.
gpt-oss-20b can replace GPT-5.1 Chat when lower sample workload cost matters most: $0.1.
gpt-oss-120b can replace GPT-5.1 Chat when lower sample workload cost matters most: $0.13.

Larger context near this budget

Llama 4 Scout offers 10M context with $0.23 sample workload cost.
Grok 4.20 Multi-Agent offers 2M context with $5 sample workload cost.
Grok 4.20 offers 2M context with $2.5 sample workload cost.
GPT-5.4 offers 1.05M context with $10 sample workload cost.

Popular competitors

No popular competitor is currently available.

Cheaper alternatives

Review low-cost models sorted by a standard 1M input plus 500K output workload.

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Larger context alternatives

Find models with larger context windows for RAG, long documents, and codebase review.

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Provider catalogs

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OpenAI catalog

Review all tracked OpenAI models before deciding whether this matchup is the right shortlist.

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Perplexity catalog

Check other Perplexity models with comparable pricing, context, or release timing.

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Exclusively available on the OpenRouter API, Sonar Pro's new Pro Search mode is Perplexity's most advanced agentic search system. It is designed for deeper reasoning and analysis. Pricing is based...