API cost decision in 10 seconds

GPT-5.5 Pro vs R1

Pick R1 for lower cost; pick GPT-5.5 Pro only if the larger context window matters more.

Page updated: 2026-05-26T15:08:08Z Data confirmed: 2026-05-26T19:08:13Z Prices normalized to USD per 1M tokens Sample workload: 1M input + 500K output

Budget verdict

Pick R1 for lower cost; pick GPT-5.5 Pro only if the larger context window matters more.

On the standard 1M input plus 500K output workload, R1 is estimated at $1.95 vs $120 for GPT-5.5 Pro, saving $118.05 (98.4% lower).

Cost-first pickR1

Context-first pickGPT-5.5 Pro

Sample savings$118.0598.4%

10x traffic gap$1180.5

GPT-5.5 Pro has more context, but R1 saves $118.05 on the standard workload. At 10x that traffic, the same price gap is about $1180.5. Use the calculator below to replace the sample workload with your own token volume.

Cost sensitivity

Workload Sensitivity

Same prices, different token mixes.

R1 stays cheaper across input-heavy, balanced, and output-heavy sample workloads.

Workload shape	Token mix	Better pick	GPT-5.5 Pro	R1
Input-heavy / RAG	5M input + 500K output	R1	$240	$4.75
Balanced workload	1M input + 1M output	R1	$210	$3.2
Output-heavy chatbot	1M input + 5M output	R1	$930	$13.2

Cheaper input R1 $30 vs $0.7 / 1M

R1 is $29.3 cheaper per 1M input tokens (97.7% lower; 42.9x difference).

Cheaper output R1 $180 vs $2.5 / 1M

R1 is $177.5 cheaper per 1M output tokens (98.6% lower; 72x difference).

Larger context GPT-5.5 Pro 1.05M vs 163.84K

GPT-5.5 Pro has 886.16K more context (6.41x larger).

Sample workload R1 $120 vs $1.95

R1 is $118.05 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

GPT-5.5 Pro Calculating… Estimated API cost

R1 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

R1 has the lower input price; R1 has the lower output price; GPT-5.5 Pro offers the larger context window. For the 1M input plus 500K output sample, R1 is cheaper for the standard workload.

For a 1M input token plus 500K output token workload, the estimated API cost is $120 for GPT-5.5 Pro and $1.95 for R1.

Best Fit

Choose GPT-5.5 Pro when you care most about larger context window.

Choose R1 when you care most about lower input-token price, and lower output-token price.

Decision Notes

On the standard 1M input plus 500K output workload, R1 is estimated at $1.95 vs $120 for GPT-5.5 Pro, saving $118.05 (98.4% lower).
R1 is $118.05 cheaper on the standard workload (98.4% lower).
R1 is $29.3 cheaper per 1M input tokens (97.7% lower; 42.9x difference).
R1 is $177.5 cheaper per 1M output tokens (98.6% lower; 72x difference).
GPT-5.5 Pro has 886.16K more context (6.41x larger).

Head-to-Head Specs

Feature	GPT-5.5 Pro (OpenAI)	R1 (DeepSeek)
Input Price prompt tokens per 1M	$30	$0.7
Completion Price per 1M tokens	$180	$2.5
Sample Workload Cost 1M input + 500K output	$120	$1.95
Context Window	1.05M	163.84K
Release Date	2026-04-24	2025-01-20
Popularity	#122	#144

Use-Case Decision Matrix

Use case	Better pick	Why
Budget-constrained production	R1	On the standard 1M input plus 500K output workload, R1 is estimated at $1.95 vs $120 for GPT-5.5 Pro, saving $118.05 (98.4% lower).
High-volume input processing	R1	Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill.
Long responses and chatbots	R1	Lower output-token price matters most when assistants generate many completion tokens.
RAG or long-document work	GPT-5.5 Pro	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-5.5 Pro when lower sample workload cost matters most: $0.
gpt-oss-20b (free) can replace GPT-5.5 Pro when lower sample workload cost matters most: $0.
gpt-oss-20b can replace GPT-5.5 Pro when lower sample workload cost matters most: $0.1.
gpt-oss-120b can replace GPT-5.5 Pro 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 offers 2M context with $2.5 sample workload cost.
Grok 4.20 Multi-Agent offers 2M context with $5 sample workload cost.

Popular competitors

DeepSeek V4 Flash · DeepSeek · #1
Hy3 preview · Tencent · #2
Claude Opus 4.7 · Anthropic · #3
Claude Sonnet 4.6 · Anthropic · #4

Cheaper alternatives

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

Open cheapest models

Larger context alternatives

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

Open largest context models

Provider catalogs

Compare models within provider hubs before choosing a final API vendor.

Open provider hubs

OpenAI catalog

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

Open OpenAI models

DeepSeek catalog

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

Open DeepSeek models

GPT-5.5 Pro

GPT-5.5 Pro is OpenAI’s high-capability model optimized for deep reasoning and accuracy on complex, high-stakes workloads. It features a 1M+ token context window (922K input, 128K output) with support for...

DeepSeek R1 is here: Performance on par with [OpenAI o1](/openai/o1), but open-sourced and with fully open reasoning tokens. It's 671B parameters in size, with 37B active in an inference pass....