GPT-6 Astra vs GPT-OSS 20B

Updated October 17, 2026. Rank says GPT-6 Astra is ahead. Price, access, and your workload can each overturn that. Public scores include evidence status and uncertainty.

Decision reading

GPT-6 Astra has the higher public score, 83.88 versus 33.32, and the 90% score intervals do not overlap. 1 results are shared. Category rows resting on Estimated evidence or different benchmark sets are marked directional and do not name a winner.

Model A

GPT-6 Astra

OpenAI

83.88/100

Supported · Public rank #3

90% interval 79.4–88.3

Model B

GPT-OSS 20B

OpenAI

33.32/100

Supported · Public rank #166

90% interval 20.0–46.6

Shared results: 1
GPT-6 Astra only: 39
GPT-OSS 20B only: 6
Like-for-like categories: 1 / 8

Supported: GPT-6 Astra and GPT-OSS 20BHow the comparison works

Which one for your work

Recommendations appear only when a shared evidence basis or an explicit operating constraint supports the call. Secondary and unsupported use cases stay disclosed below the initial list.

Long documents
Prompts that approach the documented context limit
GPT-6 Astra
GPT-6 Astra has the larger documented context window.
Confidence: documented

Show secondary and unsupported calls

Coding work
Code generation, repair, and software-engineering tasks
Not enough matched evidence
GPT-OSS 20B is scored on Estimated evidence for coding, so the reading is directional rather than like-for-like.
Confidence: limited
Agentic work
Tool use, computer use, and multi-step task completion
Not enough matched evidence
GPT-OSS 20B is scored on Estimated evidence for agentic, so the reading is directional rather than like-for-like.
Confidence: limited
Chat turn cost
1K fresh input + 500 output tokens
Not enough matched evidence
A complete comparable API-rate estimate is not available for both models.
Confidence: listed-rates
Cache-heavy agent loop cost
200K cached + 20K fresh input + 10K output tokens
Not enough matched evidence
The page does not recommend a cost winner because at least one model cannot fit the stated workload in one request. GPT-OSS 20B does not fit this workload in one request. GPT-OSS 20B has no comparable published API token rate.
Confidence: listed-rates
Repository review cost
50K fresh input + 3K output tokens
Not enough matched evidence
A complete comparable API-rate estimate is not available for both models.
Confidence: listed-rates

Which one for a specific job

Choose a job from the LLM Selector's task catalog to see the category row it rests on, under the same basis rules as the table below. A directional row stays directional; choosing a job never creates a winner.

Pick the job you would use them for

The same task catalog as the LLM Selector. Each job names the evidence surface it rests on; nothing here adds a new score.

75.5GPT-6 Astra18.2GPT-OSS 20B

Directional only · BenchAlign v5.8

GPT-6 Astra has the higher coding point estimate. Conditional score ranges do not establish rank confidence.

Coding scores combine specific tasks and setups. Match the editor, harness, and effort to your workflow.

Open the coding leaderboard Shortlist models for this job

Same basis rules as the category table below

Shape of the matched evidence

Only shared public evidence is shown. Sparse evidence stays a ruled list rather than being closed into a radar shape.

Too few matched category axes support a radar. The ruled list below shows only shared benchmark results; positions use each benchmark’s normalized display scale when available.

GPQAKnowledge
Normalized gap 24.5
GPT-6 Astra:96%
GPT-OSS 20B:71.5%
GPT-6 Astra source GPT-OSS 20B source

Bars run 0–100 on each benchmark’s normalized display scale

Category results, on a stated basis

Each row shows the public-lane category score for both models: the BenchAlign v5.8 lane for agentic, coding, and knowledge, and the weighted public rows elsewhere, with the same rank each model page reports. A row is like-for-like only when both scores rest on Supported evidence or the same weighted set. Directional and not-comparable rows remain visible, but they never receive a winner.

Knowledge

Like-for-like

GPT-6 Astra: 86.2; Supported · #3/184
GPT-OSS 20B: 33.9; Supported · #140/184
Basis: BenchAlign v5.8 lane · 7 vs 3 public rows
Reading: GPT-6 Astra leads

Agentic

Directional only

GPT-6 Astra: 74.8; Supported · #7/128
GPT-OSS 20B: 14.9; Estimated · #115/128
Basis: BenchAlign v5.8 lane · 14 vs 0 public rows
Reading: Directional only

Coding

Directional only

GPT-6 Astra: 75.5; Supported · #4/150
GPT-OSS 20B: 18.2; Estimated · #123/150
Basis: BenchAlign v5.8 lane · 6 vs 2 public rows
Reading: Directional only

Reasoning

Not comparable

GPT-6 Astra: 93.3; #1/28
GPT-OSS 20B: 49.7; Unranked · 2 rankable rows
Basis: Provisional lane · 2 vs 0 weighted rows
Reading: Not comparable

Multimodal

Not comparable

GPT-6 Astra: 87.3; Unranked · 3 rankable rows
GPT-OSS 20B: Not ranked
Basis: Provisional lane · 0 vs 0 weighted rows
Reading: Not comparable

Multilingual

Not comparable

GPT-6 Astra: Not ranked
GPT-OSS 20B: Not ranked
Basis: Provisional lane · 0 vs 0 weighted rows
Reading: Not comparable

Instruction following

Not comparable

GPT-6 Astra: Not ranked
GPT-OSS 20B: 79.2; #60/148
Basis: Provisional lane · 0 vs 0 weighted rows
Reading: Not comparable

Math

Not comparable

GPT-6 Astra: 97.3; Unranked · 2 rankable rows
GPT-OSS 20B: Not ranked
Basis: Provisional lane · 2 vs 0 weighted rows
Reading: Not comparable

Category scores with the server-provided evidence basis for GPT-6 Astra and GPT-OSS 20B
Category	GPT-6 Astra	GPT-OSS 20B	Basis	Reading
Knowledge	86.2Supported · #3/184	33.9Supported · #140/184	Like-for-likeBenchAlign v5.8 lane · 7 vs 3 public rows	GPT-6 Astra leads
Agentic	74.8Supported · #7/128	14.9Estimated · #115/128	Directional onlyBenchAlign v5.8 lane · 14 vs 0 public rows	Directional only
Coding	75.5Supported · #4/150	18.2Estimated · #123/150	Directional onlyBenchAlign v5.8 lane · 6 vs 2 public rows	Directional only
Reasoning	93.3#1/28	49.7Unranked · 2 rankable rows	Not comparableProvisional lane · 2 vs 0 weighted rows	Not comparable
Multimodal	87.3Unranked · 3 rankable rows	Not ranked	Not comparableProvisional lane · 0 vs 0 weighted rows	Not comparable
Multilingual	Not ranked	Not ranked	Not comparableProvisional lane · 0 vs 0 weighted rows	Not comparable
Instruction following	Not ranked	79.2#60/148	Not comparableProvisional lane · 0 vs 0 weighted rows	Not comparable
Math	97.3Unranked · 2 rankable rows	Not ranked	Not comparableProvisional lane · 2 vs 0 weighted rows	Not comparable

Ranks count the models scored in each category’s lane, so the agentic, coding, and knowledge denominators (BenchAlign v5.8) differ from the provisional-lane categories. Unranked scores sit on the provisional lane’s scale but never name a winner. Like-for-like rows within 0.5 points read as a practical tie.

Supported evidence per lane · bars run 0–100Methodology

What each workload costs

Three fixed token mixes turn per-token rates into comparable decisions. Each scenario states context fit and whether cached input had to fall back to the published list-input rate.

Chat turn

1K fresh input + 500 output tokens

GPT-6 Astra: $0.035; Fits in one request
GPT-OSS 20B: Self-hosted; infrastructure cost varies; Fits in one request

GPT-OSS 20B has no comparable published API token rate.

Repository review

50K fresh input + 3K output tokens

GPT-6 Astra: $0.65; Fits in one request
GPT-OSS 20B: Self-hosted; infrastructure cost varies; Fits in one request

GPT-OSS 20B has no comparable published API token rate.

Cache-heavy agent loop

200K cached + 20K fresh input + 10K output tokens

GPT-6 Astra: $0.9; Fits in one request
GPT-OSS 20B: Self-hosted; infrastructure cost varies; Does not fit in one request; Cached-input rate unavailable

GPT-OSS 20B does not fit this workload in one request. GPT-OSS 20B has no comparable published API token rate.

Cached input falls back to the list input rate only where a cached rate is unpublished

Specification differences

Sourced differences are shown directly. Missing facts stay explicit instead of being inferred from a model name or family.

SpecificationGPT-6 AstraGPT-OSS 20B

Context window

Maximum documented context; output-token limits may be lower.

GPT-6 Astra

1.05M

OpenAI GPT-6 Astra model documentation

GPT-OSS 20B

128K

API model ID

GPT-6 Astra

gpt-6-astra

OpenAI GPT-6 Astra model documentation

GPT-OSS 20B

Not sourced

Cached-input rate

A missing cached-input rate falls back to the listed input rate only in the stated workload estimate.

GPT-6 Astra

$1 per 1M cached input tokens

OpenAI GPT-6 Astra model documentation

GPT-OSS 20B

No comparable hosted API rate

Documented inputs

GPT-6 Astra

text, image

OpenAI GPT-6 Astra model documentation

GPT-OSS 20B

Not sourced

Documented outputs

GPT-6 Astra

text

OpenAI GPT-6 Astra model documentation

GPT-OSS 20B

Not sourced

Provider availability

GPT-6 Astra

Limited Availability · OpenAI Responses API, OpenAI Chat Completions API, ChatGPT Plus, Pro, Business, and Enterprise, Microsoft Azure, AWS Bedrock

OpenAI GPT-6 Astra model documentation

GPT-OSS 20B

Not sourced

Reasoning profile

GPT-6 Astra

Reasoning

GPT-OSS 20B

Non-Reasoning

Weight access

GPT-6 Astra

Proprietary

GPT-OSS 20B

Open Weight

License

GPT-6 Astra

Proprietary

GPT-OSS 20B

Open Weight

Release date

GPT-6 Astra

2026-09-03

GPT-OSS 20B

2025-08-05

If you already use one of these models

Deployment change: Both entries list OpenAI as the provider. Confirm endpoint, model ID, limits, and feature support before switching.
Quality signal: GPT-6 Astra has the higher public score, 83.88 versus 33.32, and the 90% score intervals do not overlap.
Workload cost: A complete comparable API-rate estimate is not available for both models.
Context tradeoff: GPT-6 Astra has the larger documented window (1.05M).

Run the same representative tasks against both endpoints before changing production traffic.

Questions

Which is better, GPT-6 Astra or GPT-OSS 20B?

GPT-6 Astra has the higher public score, 83.88 versus 33.32, and the 90% score intervals do not overlap. That is the clearest overall quality signal in the current public data.

Which is better for coding, GPT-6 Astra or GPT-OSS 20B?

GPT-6 Astra scores higher for coding on the public lane, 75.5 to 18.2. GPT-OSS 20B is scored on Estimated evidence for coding, so the reading is directional rather than like-for-like. BenchLM does not name a winner for coding from a directional reading; read the shared benchmark rows directly and test the models on the same task set.

Which is better for agentic tasks, GPT-6 Astra or GPT-OSS 20B?

GPT-6 Astra scores higher for agentic tasks on the public lane, 74.8 to 14.9. GPT-OSS 20B is scored on Estimated evidence for agentic tasks, so the reading is directional rather than like-for-like. BenchLM does not name a winner for agentic tasks from a directional reading; read the shared benchmark rows directly and test the models on the same task set.

Which costs less, GPT-6 Astra or GPT-OSS 20B?

Both models do not have comparable published API token rates, so this page does not name a universal price winner.

Which has the larger context window, GPT-6 Astra or GPT-OSS 20B?

GPT-6 Astra has the larger documented context window: 1.05M, compared with 128K.

Benchmark evidence

The full public result ledger is available for audit without forcing a wide desktop table onto a phone.

Browse raw public benchmark evidence46 rows

Agentic

BrowseComp
GPT-6 Astra91.5%
Source
GPT-OSS 20B—
Not directly comparable
OSWorld 2.0
GPT-6 Astra72.6%
Source
GPT-OSS 20B—
Not directly comparable
Terminal-Bench 4.0
GPT-6 Astra57.90%
Source
GPT-OSS 20B—
Not directly comparable
Terminal-Bench-Science 0.1
GPT-6 Astra64.6%
Source
GPT-OSS 20B—
Not directly comparable
ExploitGym
GPT-6 Astra42.4%
Source
GPT-OSS 20B—
Not directly comparable
Agents' Last Exam
GPT-6 Astra59.3%
Source
GPT-OSS 20B—
Not directly comparable
AutomationBench
GPT-6 Astra41.4%
Source
GPT-OSS 20B—
Not directly comparable
HLE w/ tools
GPT-6 Astra57.2%
Source
GPT-OSS 20B—
Not directly comparable
Terminal-Bench 2.1 (Vals)
GPT-6 Astra87.3%
Source
GPT-OSS 20B—
Not directly comparable
ApprenticeBench
GPT-6 Astra68%
Source
GPT-OSS 20B—
Not directly comparable
CWE-bench v1
GPT-6 Astra68.0%
Source
GPT-OSS 20B—
Not directly comparable
Hermes Index
GPT-6 Astra56.3%
Source
GPT-OSS 20B—
Not directly comparable
Hermes Bench
GPT-6 Astra73.7%
Source
GPT-OSS 20B—
Not directly comparable
MazeBench
GPT-6 Astra23%
Source
GPT-OSS 20B—
Not directly comparable

Coding

DeepSWE
GPT-6 Astra74.1%
Source
GPT-OSS 20B—
Not directly comparable
FrontierCode 1.1 Main
GPT-6 Astra53.3%
Source
GPT-OSS 20B—
Not directly comparable
FrontierCode 1.1 Extended
GPT-6 Astra64.5%
Source
GPT-OSS 20B—
Not directly comparable
FrontierSWE v2
GPT-6 Astra65.5%
Source
GPT-OSS 20B—
Not directly comparable
PostTrainBench v1.1
GPT-6 Astra44.3%
Source
GPT-OSS 20B—
Not directly comparable
Bug Hunt Bench
GPT-6 Astra45.0 fixes
Source
GPT-OSS 20B—
Not directly comparable
SWE-bench Verified
GPT-6 Astra—
GPT-OSS 20B60.7%
Source
Not directly comparable
React Native Evals
GPT-6 Astra—
GPT-OSS 20B71%
Source
Not directly comparable

Reasoning

STEMBench
GPT-6 Astra2.81
Source
GPT-OSS 20B—
Not directly comparable
ARC-AGI-1
GPT-6 Astra98.50%
Source
GPT-OSS 20B—
Not directly comparable
ARC-AGI-2
GPT-6 Astra95%
Source
GPT-OSS 20B—
Not directly comparable
ARC-AGI-3
GPT-6 Astra62.7%
Source
GPT-OSS 20B—
Not directly comparable
GeneBench-Pro
GPT-6 Astra37.8%
Source
GPT-OSS 20B—
Not directly comparable
MRCR v2 256K-512K
GPT-6 Astra100.0%
Source
GPT-OSS 20B—
Not directly comparable
MRCR v2 512K-1M
GPT-6 Astra96.3%
Source
GPT-OSS 20B—
Not directly comparable
GraphWalks BFS 256K–1M
GPT-6 Astra71.8%
Source
GPT-OSS 20B—
Not directly comparable

Multimodal

ScreenSpot Pro
GPT-6 Astra92.7%
Source
GPT-OSS 20B—
Not directly comparable
BenchCAD Vision2Code (tools)
GPT-6 Astra0.959
Source
GPT-OSS 20B—
Not directly comparable

Knowledge

GPQA
GPT-6 Astra96%
Source
GPT-OSS 20B71.5%
Source
GPT-6 Astra leads this result
GPQA-D
GPT-6 Astra96.0%
Source
GPT-OSS 20B—
Not directly comparable
HealthBench (raw)
GPT-6 Astra56.9%
Source
GPT-OSS 20B—
Not directly comparable
HealthBench (length-adjusted)
GPT-6 Astra58.3%
Source
GPT-OSS 20B—
Not directly comparable
HealthBench Professional
GPT-6 Astra64.7%
Source
GPT-OSS 20B—
Not directly comparable
HealthBench Professional (raw)
GPT-6 Astra68.2%
Source
GPT-OSS 20B—
Not directly comparable
HealthBench Hard
GPT-6 Astra36.6%
Source
GPT-OSS 20B—
Not directly comparable
MMLU
GPT-6 Astra—
GPT-OSS 20B85.3%
Source
Not directly comparable
HLE
GPT-6 Astra—
GPT-OSS 20B10.9%
Source
Not directly comparable

Instruction following

Gray Swan IPI (15 attempts)
GPT-6 Astra8.5%
Source
GPT-OSS 20B—
Not directly comparable

Math

FrontierMath v2 (Tier 4)
GPT-6 Astra97.600%
Source
GPT-OSS 20B—
Not directly comparable
FrontierMath v2 (Tiers 1-3)
GPT-6 Astra93.684%
Source
GPT-OSS 20B—
Not directly comparable
AIME 2024
GPT-6 Astra—
GPT-OSS 20B92.1%
Source
Not directly comparable
AIME 2025
GPT-6 Astra—
GPT-OSS 20B91.7%
Source
Not directly comparable

46 public results · 1 shared

Related comparisons

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Last updated October 17, 2026

GPT-6 Astra vs GPT-OSS 20B

Decision reading

Which one for your work

Long documents

Coding work

Agentic work

Chat turn cost

Cache-heavy agent loop cost

Repository review cost

Which one for a specific job

What is actually comparable

Shape of the matched evidence

Category results, on a stated basis

Knowledge

Agentic

Coding

Reasoning

Multimodal

Multilingual

Instruction following

Math

What each workload costs

Chat turn

Repository review

Cache-heavy agent loop

Specification differences

Context window

API model ID

Cached-input rate

Documented inputs

Documented outputs

Provider availability

Reasoning profile

Weight access

License

Release date

If you already use one of these models

Questions

Which is better, GPT-6 Astra or GPT-OSS 20B?

Which is better for coding, GPT-6 Astra or GPT-OSS 20B?

Which is better for agentic tasks, GPT-6 Astra or GPT-OSS 20B?

Which costs less, GPT-6 Astra or GPT-OSS 20B?

Which has the larger context window, GPT-6 Astra or GPT-OSS 20B?

Benchmark evidence

Agentic

Coding

Reasoning

Multimodal

Knowledge

Instruction following

Math

Related comparisons

Watch GPT-6 Astra vs GPT-OSS 20B