API cost decision in 10 seconds

NewGranite 4.1 8B vs GPT-5.1

Pick Granite 4.1 8B for lower cost; pick GPT-5.1 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 Granite 4.1 8B for lower cost; pick GPT-5.1 only if the larger context window matters more.

On the standard 1M input plus 500K output workload, Granite 4.1 8B is estimated at $0.1 vs $6.25 for GPT-5.1, saving $6.15 (98.4% lower).

Cost-first pickGranite 4.1 8B

Context-first pickGPT-5.1

Sample savings$6.1598.4%

10x traffic gap$61.5

GPT-5.1 has more context, but Granite 4.1 8B saves $6.15 on the standard workload. At 10x that traffic, the same price gap is about $61.5. Use the calculator below to replace the sample workload with your own token volume.

Cost sensitivity

Workload Sensitivity

Same prices, different token mixes.

Granite 4.1 8B stays cheaper across input-heavy, balanced, and output-heavy sample workloads.

Workload shape	Token mix	Better pick	Granite 4.1 8B	GPT-5.1
Input-heavy / RAG	5M input + 500K output	Granite 4.1 8B	$0.3	$11.25
Balanced workload	1M input + 1M output	Granite 4.1 8B	$0.15	$11.25
Output-heavy chatbot	1M input + 5M output	Granite 4.1 8B	$0.55	$51.25

Cheaper input Granite 4.1 8B $0.05 vs $1.25 / 1M

Granite 4.1 8B is $1.2 cheaper per 1M input tokens (96% lower; 25x difference).

Cheaper output Granite 4.1 8B $0.1 vs $10 / 1M

Granite 4.1 8B is $9.9 cheaper per 1M output tokens (99% lower; 100x difference).

Larger context GPT-5.1 131.07K vs 400K

GPT-5.1 has 268.93K more context (3.05x larger).

Sample workload Granite 4.1 8B $0.1 vs $6.25

Granite 4.1 8B is $6.15 cheaper on the standard workload (98.4% lower).

Estimate your workload cost

Your Workload Cost

Prices are normalized to USD per 1M tokens.

Monthly input tokens Monthly output tokens

Granite 4.1 8B Calculating… Estimated API cost

GPT-5.1 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

Granite 4.1 8B has the lower input price; Granite 4.1 8B has the lower output price; GPT-5.1 offers the larger context window. For the 1M input plus 500K output sample, Granite 4.1 8B is cheaper for the standard workload.

For a 1M input token plus 500K output token workload, the estimated API cost is $0.1 for Granite 4.1 8B and $6.25 for GPT-5.1.

Best Fit

Choose Granite 4.1 8B when you care most about lower input-token price, and lower output-token price.

Choose GPT-5.1 when you care most about larger context window.

Decision Notes

On the standard 1M input plus 500K output workload, Granite 4.1 8B is estimated at $0.1 vs $6.25 for GPT-5.1, saving $6.15 (98.4% lower).
Granite 4.1 8B is $6.15 cheaper on the standard workload (98.4% lower).
Granite 4.1 8B is $1.2 cheaper per 1M input tokens (96% lower; 25x difference).
Granite 4.1 8B is $9.9 cheaper per 1M output tokens (99% lower; 100x difference).
GPT-5.1 has 268.93K more context (3.05x larger).

Head-to-Head Specs

Feature	NewGranite 4.1 8B (IBM)	GPT-5.1 (OpenAI)
Input Price prompt tokens per 1M	$0.05	$1.25
Completion Price per 1M tokens	$0.1	$10
Sample Workload Cost 1M input + 500K output	$0.1	$6.25
Context Window	131.07K	400K
Release Date	2026-04-30	2025-11-13

Use-Case Decision Matrix

Use case	Better pick	Why
Budget-constrained production	Granite 4.1 8B	On the standard 1M input plus 500K output workload, Granite 4.1 8B is estimated at $0.1 vs $6.25 for GPT-5.1, saving $6.15 (98.4% lower).
High-volume input processing	Granite 4.1 8B	Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill.
Long responses and chatbots	Granite 4.1 8B	Lower output-token price matters most when assistants generate many completion tokens.
RAG or long-document work	GPT-5.1	A larger context window leaves more room for retrieved passages, conversation history, or source files.

Related Alternatives

Same-provider lower-cost swaps

Granite 4.0 Micro can replace Granite 4.1 8B when lower sample workload cost matters most: $0.07.
gpt-oss-120b (free) can replace GPT-5.1 when lower sample workload cost matters most: $0.
gpt-oss-20b (free) can replace GPT-5.1 when lower sample workload cost matters most: $0.
gpt-oss-20b can replace GPT-5.1 when lower sample workload cost matters most: $0.1.

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.
Owl Alpha offers 1.05M context with $0 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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IBM catalog

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

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OpenAI catalog

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

Open OpenAI models

Granite 4.1 8B

Granite 4.1 8B is a dense, decoder-only 8-billion-parameter language model from IBM, part of the Granite 4.1 family. It supports a 131K-token context window and is designed for enterprise tasks...

GPT-5.1

GPT-5.1 is the latest frontier-grade model in the GPT-5 series, offering stronger general-purpose reasoning, improved instruction adherence, and a more natural conversational style compared to GPT-5. It uses adaptive reasoning...