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Model Comparison

Seed 2.1 Turbo vs gpt-oss-20bWhich Is Better in 2026?

ByteDance Seed: Seed 2.1 Turbo logoByteDance•OpenAI: gpt-oss-20b logoOpenAI

Seed 2.1 Turbo vs gpt-oss-20b: which should you choose in 2026?

Seed 2.1 Turbo (by ByteDance) and gpt-oss-20b (by OpenAI) are compared below. Here is how they stack up on benchmarks, price, and capabilities, and which one to pick in 2026.

There are not enough shared, protocol-compatible benchmark results to declare a performance leader.

gpt-oss-20b is about 18.2× cheaper on a blended 3:1 input/output basis ($0.055 vs $1.00 per 1M tokens).

Seed 2.1 Turbo has the larger context window (262,144 tokens vs 131,072 tokens).

Choose Seed 2.1 Turbo if…

  • • you work with longer documents, transcripts, or codebases
  • • you need image inputs

Choose gpt-oss-20b if…

  • • lower blended API cost matters for your workload

The benchmark count includes only results measured with a matching benchmark version and protocol. Arena scores are shown separately. Missing, preliminary, and incompatible data is not treated as a controlled win. Published point-score comparisons are labeled separately when protocol details are incomplete. For text-output models, the verdict also compares token pricing and context windows.

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Performance benchmarks

Every value links to its source. A dash means that no reviewed result is available for that exact model and protocol.

Seed 2.1 Turbo and gpt-oss-20b benchmark results
BenchmarkSeed 2.1 Turbogpt-oss-20b
AutomationBench-AA

A 657-task benchmark of multi-step work across simulated SaaS applications in six business domains. The Artificial Analysis protocol reports a guardrail-aware score and is distinct from both the public Zapier split and the unrelated dynamic AutoBench framework.

Guardrail-aware score

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BrowseComp

A benchmark of difficult, verifiable information-seeking questions designed to measure an agent's ability to locate hard-to-find facts through web browsing.

Accuracy

——
OSWorld-Verified

A verified computer-use benchmark in which multimodal agents operate desktop applications and are graded from the resulting environment state.

Mean task reward

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SWE-Bench Verified

A human-validated subset of real GitHub issues used to measure whether a coding agent can produce repository patches that resolve the associated tests.

Resolved

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Terminal-Bench 2.1

Version 2.1 of the benchmark for completing realistic tasks in terminal environments. Harness, resource limits, and attempt count are part of the protocol.

Mean task success

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AutoBench

A dynamic LLM evaluation framework in which models generate questions, answer them, and participate in reciprocal peer assessment. AutoBench is distinct from Zapier's AutomationBench.

Weighted peer-assessment score

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GPQA Diamond

The highest-quality subset of Graduate-Level Google-Proof Q&A, designed to test expert-level scientific reasoning in biology, physics, and chemistry.

Accuracy

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Humanity's Last Exam

A 2,500-question expert-level benchmark spanning dozens of academic fields. Tool-assisted and no-tools results are separate protocols and must not be merged.

Accuracy

——
Arena preference scores
Arena (Text)

Human preference score

—
1318 ±6

Benchmark sources

Reviewed evidence last updated 2026-08-09. Arena data last refreshed Aug 23, 2026.

Pricing, capabilities, and model facts

Seed 2.1 Turbo and gpt-oss-20b model facts
FeatureSeed 2.1 Turbogpt-oss-20b
Context & model facts
DeveloperByteDanceOpenAI
API providerByteDance SeedOpenAI
Input context262,144 tokens131,072 tokens
Maximum output262,144 tokens131,072 tokens
Released——
Added to WritingmateAug 12, 2026Aug 5, 2025
LicenseNot availableNot available
Knowledge cutoff—2024-06-30
Capabilities
InputsText, Image, VideoText
OutputsTextText
Provider endpoint accepts tool parametersYesYes
ReasoningYesYes
VisionYesNo
Image GenerationNoNo
Video GenerationNoNo
API pricing
Input (per 1M tokens)$0.50$0.03
Output (per 1M tokens)$2.50$0.13
Blended 3:1 input/output$1.00$0.055
API performance
p95 latencyNot measuredNot measured
Output throughputNot measuredNot measured
Writingmate shows API performance only when both models have enough observations from the same measurement window, prompt profile, and provider. Third-party latency values are not copied into this table.

Data sources

  • Writingmate model catalog (pricing, limits, and availability)

Catalog data last updated Aug 12, 2026.

Why Pay for Multiple Subscriptions?

Comparing Seed 2.1 Turbo from ByteDance with gpt-oss-20b from OpenAI? Instead of managing separate API keys and subscriptions, get both with Writingmate.

Subscription-plan access for Seed 2.1 Turbo and gpt-oss-20b
PlanPriceSeed 2.1 Turbogpt-oss-20bAI ImagesAI Video
Writingmate Pro
Most popular
$20/moIncludedIncludedNano Banana Pro, FLUX.2, DALL-E & moreSora 2, VEO 3.1
Writingmate Ultimate
Power users
$60/moIncludedIncludedNano Banana Pro, FLUX.2, DALL-E & moreSora 2, VEO 3.1
View Plans & Pricing

Seed 2.1 Turbo vs gpt-oss-20b FAQ

Which is better, Seed 2.1 Turbo or gpt-oss-20b?

There are not enough shared, protocol-compatible benchmark results to declare a performance leader. gpt-oss-20b is about 18.2× cheaper on a blended 3:1 input/output basis ($0.055 vs $1.00 per 1M tokens). Seed 2.1 Turbo has the larger context window (262,144 tokens vs 131,072 tokens).

Which model is cheaper to use through an API?

gpt-oss-20b is about 18.2× cheaper on a blended 3:1 input/output basis ($0.055 vs $1.00 per 1M tokens).

Which model supports more context?

Seed 2.1 Turbo has the larger context window (262,144 tokens vs 131,072 tokens).

Can I switch between Seed 2.1 Turbo and gpt-oss-20b?

Yes. Use the model selector on this page to open any current Writingmate model comparison. You can also run the same prompt with both models in Writingmate.