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GPT-1 vs GPT-2

GPT-1 (2018) and GPT-2 (2019) are compact production models from OpenAI. GPT-1 ships a 512-token context window, while GPT-2 ships a 1K-token context window. This comparison covers specs, pricing, capabilities, benchmarks, provider availability, and production fit. It focuses on practical selection signals rather than broad model-family marketing. The goal is to make the tradeoff clear before deeper testing.

GPT-2 is safer overall; choose GPT-1 when provider fit matters.

Decision scorecard

Local evidence first
SignalGPT-1GPT-2
Decision fitGeneralGeneral
Context window5121K
Cheapest output--
Provider routes0 tracked1 tracked
Shared benchmarks0 rows0 rows

Decision tradeoffs

Choose GPT-1 when...
  • Use GPT-1 when your own prompt tests beat the comparison signals; the local data does not show a decisive standalone advantage yet.
Choose GPT-2 when...
  • GPT-2 has the larger context window for long prompts, retrieval packs, or transcript analysis.
  • GPT-2 has broader tracked provider coverage for fallback and procurement flexibility.

Monthly cost at traffic

Estimate token spend from the cheapest tracked input and output prices on this page.

GPT-1

Unavailable

No complete token price in local provider data

GPT-2

Unavailable

No complete token price in local provider data

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

Switch friction

GPT-1 -> GPT-2
  • No overlapping tracked provider route is sourced for GPT-1 and GPT-2; plan for SDK, billing, or endpoint changes.
GPT-2 -> GPT-1
  • No overlapping tracked provider route is sourced for GPT-2 and GPT-1; plan for SDK, billing, or endpoint changes.

Specs

Specification
Released2018-06-112019-02-14
Context window5121K
Parameters120M124M
Architecturedecoder onlydecoder only
LicenseUnknownUnknown
Knowledge cutoff-2017-12

Pricing and availability

Pricing attributeGPT-1GPT-2
Input price--
Output price--
Providers-

Pricing not yet sourced for either model.

Capabilities

CapabilityGPT-1GPT-2
VisionNoNo
MultimodalNoNo
ReasoningNoNo
Function callingNoNo
Tool useNoNo
Structured outputsNoNo
Code executionNoNo

Benchmarks

No shared benchmark rows are currently sourced for this pair.

Deep dive

The capability footprint is close: both models cover the core production surface. That makes context budget, benchmark fit, and provider maturity more important than a simple checklist. If your application depends on one integration detail, verify it against the provider route you plan to use, not just the base model listing.

Pricing coverage is uneven: GPT-1 has no token price sourced yet and GPT-2 has no token price sourced yet. Provider availability is 0 tracked routes versus 1. Treat unknown pricing as an integration gap, then verify the route you will actually call before estimating production spend.

Choose GPT-1 when provider fit are central to the workload. Choose GPT-2 when long-context analysis, 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-1 or GPT-2?

GPT-2 supports 1K tokens, while GPT-1 supports 512 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-1 or GPT-2 open source?

GPT-1 is listed under Unknown. GPT-2 is listed under Unknown. License labels affect whether you can self-host, redistribute weights, or rely only on hosted APIs, so confirm the upstream license before deployment.

Where can I run GPT-1 and GPT-2?

GPT-1 is available on the tracked providers still being sourced. GPT-2 is available on Azure OpenAI. 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.

When should I pick GPT-1 over GPT-2?

GPT-2 is safer overall; choose GPT-1 when provider fit matters. If your workload also depends on provider fit, start with GPT-1; if it depends on long-context analysis, run the same evaluation with GPT-2.

Continue comparing

Last reviewed: 2026-04-27. Data sourced from public model cards and provider documentation.