LLM Reference

GPT-5.3-Codex-Spark vs Xiaomi MiMo-V2.5-Pro

GPT-5.3-Codex-Spark (2026) and Xiaomi MiMo-V2.5-Pro (2026) are agentic coding models from OpenAI and Xiaomi. GPT-5.3-Codex-Spark ships a 131k-token context window, while Xiaomi MiMo-V2.5-Pro ships a 1.05m-token context window. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads. It focuses on practical selection signals rather than broad model-family marketing.

Xiaomi MiMo-V2.5-Pro fits 8x more tokens; pick it for long-context work and GPT-5.3-Codex-Spark for tighter calls.

Decision scorecard

Local evidence first
SignalGPT-5.3-Codex-SparkXiaomi MiMo-V2.5-Pro
Best forcustom coding agents, code generation, and tool loopscustom coding agents, code generation, and tool loops
Decision fitCoding, RAG, and AgentsCoding, RAG, and Agents
Context window131k1.05m
Cheapest output-$0.87/1M tokens
Provider routes1 tracked3 tracked
Shared benchmarks0 rows0 rows

Decision tradeoffs

Choose GPT-5.3-Codex-Spark when...
  • GPT-5.3-Codex-Spark uniquely exposes Code execution in local model data.
  • Local decision data tags GPT-5.3-Codex-Spark for Coding, RAG, and Agents.
Choose Xiaomi MiMo-V2.5-Pro when...
  • Xiaomi MiMo-V2.5-Pro has the larger context window for long prompts, retrieval packs, or transcript analysis.
  • Xiaomi MiMo-V2.5-Pro has broader tracked provider coverage for fallback and procurement flexibility.
  • Local decision data tags Xiaomi MiMo-V2.5-Pro 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.

GPT-5.3-Codex-Spark

Unavailable

No complete token price in local provider data

Xiaomi MiMo-V2.5-Pro

$566

Cheapest tracked route/tier: OpenRouter

Cost delta unavailable until both models have sourced input and output token prices.

Switch friction

GPT-5.3-Codex-Spark -> Xiaomi MiMo-V2.5-Pro
  • No overlapping tracked provider route is sourced for GPT-5.3-Codex-Spark and Xiaomi MiMo-V2.5-Pro; plan for SDK, billing, or endpoint changes.
  • Check replacement coverage for Code execution before moving production traffic.
Xiaomi MiMo-V2.5-Pro -> GPT-5.3-Codex-Spark
  • No overlapping tracked provider route is sourced for Xiaomi MiMo-V2.5-Pro and GPT-5.3-Codex-Spark; plan for SDK, billing, or endpoint changes.
  • GPT-5.3-Codex-Spark adds Code execution in local capability data.

Specs

Specification
Released2026-02-122026-04-22
Context window131k1.05m
Parameters1T
Architecturedecoder onlymixture of experts
LicenseProprietaryProprietary
OpennessProprietaryProprietary
Commercial useCommercial use with conditionsCommercial use with conditions
Knowledge cutoff--

Pricing and availability

Pricing attributeGPT-5.3-Codex-SparkXiaomi MiMo-V2.5-Pro
Input price-$0.43/1M tokens
Output price-$0.87/1M tokens
Providers

Capabilities

CapabilityGPT-5.3-Codex-SparkXiaomi MiMo-V2.5-Pro
VisionNoNo
MultimodalNoNo
ReasoningNoNo
Function callingYesYes
Tool useYesYes
Structured outputsYesYes
Code executionYesNo
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 code execution: GPT-5.3-Codex-Spark. Both models share function calling, tool use, and structured outputs, 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.

Pricing coverage is uneven: GPT-5.3-Codex-Spark has no token price sourced yet and Xiaomi MiMo-V2.5-Pro has $0.43/1M input tokens. Provider availability is 1 tracked routes versus 3. Treat unknown pricing as an integration gap, then verify the route you will actually call before estimating production spend.

Choose GPT-5.3-Codex-Spark when coding workflow support are central to the workload. Choose Xiaomi MiMo-V2.5-Pro 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. For teams standardizing a stack, that distinction is often the difference between a benchmark win and a reliable deployment.

FAQ

Which has a larger context window, GPT-5.3-Codex-Spark or Xiaomi MiMo-V2.5-Pro?

Xiaomi MiMo-V2.5-Pro supports 1.05m tokens, while GPT-5.3-Codex-Spark supports 131k tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.

Is GPT-5.3-Codex-Spark or Xiaomi MiMo-V2.5-Pro open source?

GPT-5.3-Codex-Spark is listed under Proprietary. Xiaomi MiMo-V2.5-Pro 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 function calling, GPT-5.3-Codex-Spark or Xiaomi MiMo-V2.5-Pro?

Both GPT-5.3-Codex-Spark and Xiaomi MiMo-V2.5-Pro expose function calling. 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.

Which is better for tool use, GPT-5.3-Codex-Spark or Xiaomi MiMo-V2.5-Pro?

Both GPT-5.3-Codex-Spark and Xiaomi MiMo-V2.5-Pro expose tool use. 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.

Which is better for structured outputs, GPT-5.3-Codex-Spark or Xiaomi MiMo-V2.5-Pro?

Both GPT-5.3-Codex-Spark and Xiaomi MiMo-V2.5-Pro expose structured outputs. 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 GPT-5.3-Codex-Spark and Xiaomi MiMo-V2.5-Pro?

GPT-5.3-Codex-Spark is available on OpenAI API. Xiaomi MiMo-V2.5-Pro is available on OpenRouter, Xiaomi, and Novita AI. Provider coverage can affect latency, region availability, compliance posture, and fallback options. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.

Continue comparing

Last reviewed: 2026-06-04. Data sourced from public model cards and provider documentation.