DeepSeek R1 vs Gemini 3.1 Pro preview

DeepSeek R1 (Azure AI Foundry, 128,000-token context) versus Gemini 3.1 Pro preview (Google Vertex AI, 1,048,576-token context). DeepSeek R1 is cheaper by 52% on a blended token mix. Gemini 3.1 Pro preview uniquely supports function calling and vision input. Across 3 public benchmarks we tracked, DeepSeek R1 wins 0 and Gemini 3.1 Pro preview wins 3. Use the live calculator below to plug your real usage shape into both, then route the winner via Agent Command Center for shadow A/B without code changes.

Bottom line — DeepSeek R1 vs Gemini 3.1 Pro preview

DeepSeek R1 and Gemini 3.1 Pro preview target overlapping workloads but differ sharply on economics. DeepSeek R1 runs roughly 52% cheaper on a blended input-plus-output token mix, which translates to approximately $5,910 per month at mid-market volume (100K requests/day). The gap compounds at enterprise scale, making the cost axis the first filter most teams apply when deciding between these two models.

Gemini 3.1 Pro preview ships a 1,048,576-token context window, 8.2x larger than DeepSeek R1's 128,000 tokens. That headroom matters for long-document RAG pipelines, multi-turn agent sessions that accumulate tool-call history, and codebases where the entire repository needs to fit in a single prompt. If your average prompt stays under 128,000 tokens, the extra context on Gemini 3.1 Pro preview is insurance you may never use — and DeepSeek R1 may win on other axes.

On capability surface area, the models diverge: Gemini 3.1 Pro preview supports function calling where the other does not; Gemini 3.1 Pro preview supports vision input where the other does not; Gemini 3.1 Pro preview supports audio input where the other does not. These differences are binary — either your workload needs the capability or it does not. Check whether any critical path in your agent pipeline depends on a capability only one model provides before committing to a migration.

Across 3 public benchmarks, DeepSeek R1 leads on 0 and Gemini 3.1 Pro preview leads on 3. The widest gap is on arena-elo, where Gemini 3.1 Pro preview scores 131.0 points higher. Benchmarks are noisy and task-dependent — a model that leads on arena-elo may trail on code generation. The safest approach is to run both models on your own golden set before treating any benchmark as decisive.

For teams evaluating both models, the recommended path is a shadow A/B test: route production traffic through an OpenAI-compatible gateway, mirror a percentage to the candidate model, score both responses with an automated evaluator (faithfulness, tool-call correctness, latency), and compare cohort-level metrics over two weeks. Future AGI Agent Command Center supports this pattern with a single `base_url` change and built-in evaluators from the ai-evaluation SDK.

Side-by-side cost

Live workload comparison

Same workload run through both models. The cheaper one is highlighted.

3,000
01,048,576
400
065,536
5,000
01,000,000
Azure AI Foundry
$945/mo
Input $1.35/M · Output $5.40/M
Google Vertex AI
$1,644/mo
Input $2.00/M · Output $12.00/M
At this workload, DeepSeek R1 is 42% cheaper than Gemini 3.1 Pro preview — a savings of $699/month ($8,382/year).
Production recipe — Agent Command Center
strategy: cost-optimized
primary:
  model: deepseek-r1
  provider: azure-ai-foundry
fallback:
  model: gemini-3-1-pro-preview
  provider: vertex-ai
shadow: { sample_rate: 0.05 }   # mirror 5% of traffic to compare quality live
DeepSeek R1 Gemini 3.1 Pro preview
Input price $1.35/M $2.00/M
Output price $5.40/M $12.00/M
Context window 128,000 1,048,576
Max output 8,192 65,536
Function calling
Vision
Audio input
Reasoning
Prompt caching
Structured output
Pricing verified Jun 2, 2026 Jun 2, 2026
Cheaper option
~52% cheaper than the priciest in this pair
Larger context
1,048,576 tokens
More capabilities
6 of 6 capability flags advertised

Benchmark comparison

Side-by-side public benchmark scores. Greener bar = winner.

Chatbot Arena ELOgeneral
DeepSeek R1
1,361
Gemini 3.1 Pro preview
1,492
MATH-500math
DeepSeek R1
97.3%
Gemini 3.1 Pro preview
GPQA Diamondreasoning⚠ different settings
DeepSeek R1
71.5%
Gemini 3.1 Pro preview
94.3%
MMLUgeneral
DeepSeek R1
90.8%
Gemini 3.1 Pro preview
τ-bench (retail)agent
DeepSeek R1
Gemini 3.1 Pro preview
90.8%
HumanEvalcode
DeepSeek R1
89.7%
Gemini 3.1 Pro preview
MMLU-Proreasoning
DeepSeek R1
84.0%
Gemini 3.1 Pro preview
SWE-bench Verifiedagent⚠ different settings
DeepSeek R1
49.2%
Gemini 3.1 Pro preview
80.6%
MMMU-Promultimodal
DeepSeek R1
Gemini 3.1 Pro preview
80.5%
AIME 2024math
DeepSeek R1
79.8%
Gemini 3.1 Pro preview
ARC-AGI-2reasoning
DeepSeek R1
Gemini 3.1 Pro preview
77.1%
LiveCodeBenchcode
DeepSeek R1
65.9%
Gemini 3.1 Pro preview
SciCodecode
DeepSeek R1
Gemini 3.1 Pro preview
59.0%
Aider Polyglotcode
DeepSeek R1
57.0%
Gemini 3.1 Pro preview
Humanity's Last Examreasoning
DeepSeek R1
Gemini 3.1 Pro preview
44.4%

Cost at scale: monthly spend at three usage volumes

Estimated monthly cost assuming 1,000 input + 200 output tokens per request — a realistic chat-agent shape. Adjust your own usage in the calculator at the top of this page for an exact number.

Scale DeepSeek R1 Gemini 3.1 Pro preview Delta
Startup
10K requests/day
$729 /mo $1,320 /mo $591/mo
Mid-market
100K requests/day
$7,290 /mo $13,200 /mo $5,910/mo
Enterprise
1M requests/day
$72,900 /mo $132,000 /mo $59,100/mo

At enterprise scale (1M requests/day), a difference of even ~10% in unit price compounds into thousands of dollars per month. Cached input pricing and batch tiers can shift this further — both are surfaced on each model's own page.

When to choose which

Picked from the data above — not vendor marketing. Match the rules to your workload, not the other way around.

Choose DeepSeek R1

You're cost-sensitive at scale — DeepSeek R1 runs ~52% cheaper on a blended in+out token mix, compounding into thousands of dollars per month at production volume.

Choose Gemini 3.1 Pro preview

Your workload needs long context — Gemini 3.1 Pro preview fits 1,048,576 tokens versus the other model's 128,000, enough headroom for full books, large codebases, or 100+ page documents in one shot.

Choose Gemini 3.1 Pro preview

Your inputs include screenshots, diagrams, or product photos — Gemini 3.1 Pro preview accepts image input natively, the other doesn't.

Choose Gemini 3.1 Pro preview

Your agent listens to calls or voice notes — Gemini 3.1 Pro preview accepts audio input directly, the other requires an ASR preprocessing hop.

Choose Gemini 3.1 Pro preview

You re-send the same large system prompt across requests — Gemini 3.1 Pro preview supports prompt caching, cutting input cost on repeat hits.

Choose Gemini 3.1 Pro preview

Your agent calls tools or APIs — Gemini 3.1 Pro preview supports function calling natively, the other model needs a parser shim.

Choose Gemini 3.1 Pro preview

On arena-elo, Gemini 3.1 Pro preview scores 131.0 points higher — if your workload pattern matches that benchmark's task shape, the gap is meaningful.

Capability diff — what you gain and lose on the swap

A specific list of what each model has that the other doesn't. If your workload depends on a row in Only DeepSeek R1, switching to Gemini 3.1 Pro preview means re-architecting that path (and vice versa).

Only on DeepSeek R1
Nothing — everything DeepSeek R1 ships is also on Gemini 3.1 Pro preview.
Only on Gemini 3.1 Pro preview
  • • Function calling
  • • Vision input
  • • Audio input
  • • PDF input
  • • Structured output (JSON schema)
  • • Prompt caching
Capabilities both share (2)
  • ✓ Streaming
  • ✓ Native reasoning mode

Benchmark winners — by the numbers

For each public benchmark that has scores for both models, the higher score and the size of the gap. Benchmarks are noisy — treat anything under a 2-point delta as effectively tied.

Benchmark DeepSeek R1 Gemini 3.1 Pro preview Winner Δ
arena-elo 1361.0 1492.0 Gemini 3.1 Pro preview +131.0
gpqa-diamond 71.5 94.3 Gemini 3.1 Pro preview +22.8
swe-bench-verified 49.2 80.6 Gemini 3.1 Pro preview +31.4

Migration considerations

Concrete differences to wire through your stack before you flip traffic from one to the other.

  • Context window changes up 719% when moving from DeepSeek R1 (128,000) to Gemini 3.1 Pro preview (1,048,576). Re-check any prompt that relies on cramming long history or documents.
  • Max output tokens differ: 8,192 on DeepSeek R1 vs 65,536 on Gemini 3.1 Pro preview. Long-form generation tasks may truncate differently — adjust streaming UI and chunking accordingly.
  • Gemini 3.1 Pro preview has capabilities DeepSeek R1 lacks: Function calling, Vision input, Audio input, PDF input, Structured output (JSON schema), Prompt caching. Worth wiring through the agent design before commit.
  • Provider changes from Azure AI Foundry to Google Vertex AI. API authentication, rate-limit policy, regional availability, and billing all shift. Most teams route through an OpenAI-compatible gateway (e.g., Future AGI Agent Command Center) so the swap is a single `base_url` change instead of an SDK rewrite.

How to A/B test DeepSeek R1 vs Gemini 3.1 Pro preview in production

If you're stuck between the two, run them side-by-side on real traffic. Four steps the Future AGI team uses internally:

  1. 1. Point your existing OpenAI SDK at https://gateway.futureagi.com/v1. No code change beyond base_url and a virtual key.
  2. 2. Mark DeepSeek R1 primary, mirror 20% of traffic to Gemini 3.1 Pro preview in shadow mode. Both responses are logged; only the primary is served to users.
  3. 3. Score every shadow response with an evaluator — faithfulness, tool-call correctness, response latency, cost. Built-in evaluators in ai-evaluation cover the common axes.
  4. 4. Compare cohort-level metrics after two weeks. Switch primary when the candidate wins on what matters to your workload — and stays within your latency budget.

Full walkthrough on the Agent Command Center page.

FAQ — DeepSeek R1 vs Gemini 3.1 Pro preview

Which is cheaper, DeepSeek R1 or Gemini 3.1 Pro preview?

DeepSeek R1 is cheaper by roughly 52% on a blended input + output token mix. Input prices are $1.35/M for DeepSeek R1 versus $2.00/M for Gemini 3.1 Pro preview; output prices are $5.40/M versus $12.00/M. The exact savings depend on your input:output ratio — use the live calculator above to plug in your own request shape.

What is the context window of DeepSeek R1 versus Gemini 3.1 Pro preview?

DeepSeek R1 supports up to 128,000 tokens of context. Gemini 3.1 Pro preview supports up to 1,048,576 tokens. Gemini 3.1 Pro preview has the larger window by a factor of 8.2x, which matters for long-document RAG, multi-turn agent sessions, and tasks that need to keep an entire codebase in working memory.

Do DeepSeek R1 and Gemini 3.1 Pro preview both support tool calling?

Only Gemini 3.1 Pro preview supports native function calling. The other model can still be made to call tools through a structured-output workaround, but the reliability of that pattern is lower than native support.

Can DeepSeek R1 and Gemini 3.1 Pro preview process images?

Gemini 3.1 Pro preview accepts native image input. DeepSeek R1 does not — you would need to route image-heavy workloads through Gemini 3.1 Pro preview or add a separate vision model in front of DeepSeek R1.

Which model supports prompt caching for cost reduction?

Gemini 3.1 Pro preview supports prompt caching; the other does not. If your agent has a stable system prompt + retrieval context block that repeats across requests, Gemini 3.1 Pro preview gives you a 50–90% discount on those repeated input tokens at the provider level.

When should I choose DeepSeek R1 over Gemini 3.1 Pro preview?

You're cost-sensitive at scale — DeepSeek R1 runs ~52% cheaper on a blended in+out token mix, compounding into thousands of dollars per month at production volume.

When should I choose Gemini 3.1 Pro preview over DeepSeek R1?

Your workload needs long context — Gemini 3.1 Pro preview fits 1,048,576 tokens versus the other model's 128,000, enough headroom for full books, large codebases, or 100+ page documents in one shot. Your inputs include screenshots, diagrams, or product photos — Gemini 3.1 Pro preview accepts image input natively, the other doesn't. Your agent listens to calls or voice notes — Gemini 3.1 Pro preview accepts audio input directly, the other requires an ASR preprocessing hop. You re-send the same large system prompt across requests — Gemini 3.1 Pro preview supports prompt caching, cutting input cost on repeat hits. Your agent calls tools or APIs — Gemini 3.1 Pro preview supports function calling natively, the other model needs a parser shim. On arena-elo, Gemini 3.1 Pro preview scores 131.0 points higher — if your workload pattern matches that benchmark's task shape, the gap is meaningful.

How do I A/B test DeepSeek R1 against Gemini 3.1 Pro preview in production?

Route both through an OpenAI-compatible gateway like Future AGI Agent Command Center with shadow mode enabled. Send 100% of traffic to your primary model, mirror 10–20% to the candidate, score every response with an evaluator (faithfulness, tool-call correctness, response time), and compare cohort-level metrics for two weeks. Switch when the candidate wins on the metrics that matter to your workload and stays within your latency budget.