LLM Reference

DeepSeek R1 Basic vs GPT-5.3-Codex

DeepSeek R1 Basic (2025) and GPT-5.3-Codex (2026) compare a standalone API model against a coding-specialized model. DeepSeek R1 Basic ships a 160K-token context window, while GPT-5.3-Codex ships a 400K-token context window. On pricing, DeepSeek R1 Basic costs $0.56/1M input tokens versus $1.75/1M for the alternative. This page treats the result as workflow and deployment fit, not a universal model winner.

Treat this as a product-type comparison: DeepSeek R1 Basic is standalone API model, while GPT-5.3-Codex is coding-specialized model. Choose based on workflow fit before reading any benchmark or price row as decisive.

Decision scorecard

Local evidence first
SignalDeepSeek R1 BasicGPT-5.3-Codex
Product typeStandalone API modelCoding-specialized model
Best forreasoning-heavy appscustom coding agents, code generation, and tool loops
Decision fitLong contextCoding, RAG, and Agents
Context window160K400K
Cheapest output$1.68/1M tokens$14/1M tokens
Provider routes1 tracked3 tracked
Shared benchmarks0 rows0 rows

Decision tradeoffs

Choose DeepSeek R1 Basic when...
  • DeepSeek R1 Basic has the lower cheapest tracked output price at $1.68/1M tokens.
  • Local decision data tags DeepSeek R1 Basic for Long context.
Choose GPT-5.3-Codex when...
  • GPT-5.3-Codex has the larger context window for long prompts, retrieval packs, or transcript analysis.
  • GPT-5.3-Codex has broader tracked provider coverage for fallback and procurement flexibility.
  • GPT-5.3-Codex uniquely exposes Vision, Function calling, and Tool use in local model data.
  • Local decision data tags GPT-5.3-Codex for Coding, RAG, and Agents.

Monthly cost at traffic

Estimate token spend from the cheapest tracked input and output route or tier on this page.

Lower estimate DeepSeek R1 Basic

DeepSeek R1 Basic

$868

Cheapest tracked route/tier: Fireworks AI

GPT-5.3-Codex

$4,900

Cheapest tracked route/tier: OpenRouter

Estimated monthly gap: $4,032. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.

Switch friction

DeepSeek R1 Basic -> GPT-5.3-Codex
  • No overlapping tracked provider route is sourced for DeepSeek R1 Basic and GPT-5.3-Codex; plan for SDK, billing, or endpoint changes.
  • GPT-5.3-Codex is $12.32/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
  • GPT-5.3-Codex adds Vision, Function calling, and Tool use in local capability data.
GPT-5.3-Codex -> DeepSeek R1 Basic
  • No overlapping tracked provider route is sourced for GPT-5.3-Codex and DeepSeek R1 Basic; plan for SDK, billing, or endpoint changes.
  • DeepSeek R1 Basic is $12.32/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
  • Check replacement coverage for Vision, Function calling, and Tool use before moving production traffic.

Specs

Specification
Released2025-01-012026-02-05
Context window160K400K
Parameters671B
Architecturedecoder onlydecoder only
LicenseOpen SourceProprietary
Knowledge cutoff-2025-08

Pricing and availability

Pricing attributeDeepSeek R1 BasicGPT-5.3-Codex
Input price$0.56/1M tokens$1.75/1M tokens
Output price$1.68/1M tokens$14/1M tokens
Providers

Capabilities

CapabilityDeepSeek R1 BasicGPT-5.3-Codex
VisionNoYes
MultimodalNoNo
ReasoningYesYes
Function callingNoYes
Tool useNoYes
Structured outputsNoYes
Code executionNoYes
IDE integrationNoNo
Computer useNoNo
Parallel agentsNoNo

Benchmarks

No shared benchmark rows are currently sourced for this pair.

Deep dive

The capability footprint differs most on vision: GPT-5.3-Codex, function calling: GPT-5.3-Codex, tool use: GPT-5.3-Codex, structured outputs: GPT-5.3-Codex, and code execution: GPT-5.3-Codex. Both models share reasoning mode, so the practical split is not just feature count. Use those differences to decide whether the page is about raw model quality, agentic coding support, multimodal ingestion, or predictable structured API behavior.

For cost, DeepSeek R1 Basic lists $0.56/1M input and $1.68/1M output tokens on the cheapest tracked provider, while GPT-5.3-Codex lists $1.75/1M input and $14/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts DeepSeek R1 Basic lower by about $4.53 per million blended tokens. Availability is 1 providers versus 3, so concentration risk also matters.

Choose DeepSeek R1 Basic when provider fit and lower input-token cost are central to the workload. Choose GPT-5.3-Codex when coding workflow support, larger context windows, and broader provider choice are more important. For production, rerun your own prompts through the exact provider, region, and tool stack you plan to ship. This keeps the decision grounded in measurable tradeoffs instead of brand-level assumptions. It also helps separate model capability from provider packaging, which can change cost and latency.

FAQ

Which has a larger context window, DeepSeek R1 Basic or GPT-5.3-Codex?

GPT-5.3-Codex supports 400K tokens, while DeepSeek R1 Basic supports 160K tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible.

Which is cheaper, DeepSeek R1 Basic or GPT-5.3-Codex?

DeepSeek R1 Basic is cheaper on tracked token pricing. DeepSeek R1 Basic costs $0.56/1M input and $1.68/1M output tokens. GPT-5.3-Codex costs $1.75/1M input and $14/1M output tokens. Provider discounts or batch pricing can still change the final bill.

Is DeepSeek R1 Basic or GPT-5.3-Codex open source?

DeepSeek R1 Basic is listed under Open Source. GPT-5.3-Codex is listed under Proprietary. License labels affect whether you can self-host, redistribute weights, or rely only on hosted APIs, so confirm the upstream license before deployment.

Which is better for vision, DeepSeek R1 Basic or GPT-5.3-Codex?

GPT-5.3-Codex has the clearer documented vision signal in this comparison. If vision is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.

Which is better for reasoning mode, DeepSeek R1 Basic or GPT-5.3-Codex?

Both DeepSeek R1 Basic and GPT-5.3-Codex expose reasoning mode. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.

Where can I run DeepSeek R1 Basic and GPT-5.3-Codex?

DeepSeek R1 Basic is available on Fireworks AI. GPT-5.3-Codex is available on OpenRouter, OpenAI API, and Vercel AI Gateway. Provider coverage can affect latency, region availability, compliance posture, and fallback options.

Continue comparing

Last reviewed: 2026-05-22. Data sourced from public model cards and provider documentation.