AI Models · Open-Source vs Paid

gpt-oss-120b Open vs PEPerceptron Mk1.5 Paid

gpt-oss-120b vs Perceptron Mk1.5 compared — price per token, context window, multimodality, openness and which to choose. Can the open-source model replace the paid one? Full 2026 breakdown.

Prices & specs refreshed from live data · olud.ai

Open-model prices = cheapest provider via OpenRouter; official maker rates may be higher.

gpt-oss-120bOpenOpenAI
$0.15 /M input
$0.6 /M outputNo per-token fees if you self-host
TypeOpen-weight
Context window131K tokens
MultimodalNo
Self-hostYes
PEPerceptron Mk1.5PaidPerceptron
$0.15 /M input
$1.5 /M outputManaged API (no infra to run)
TypeProprietary
Context window37K tokens
MultimodalYes
Self-hostNo
Choose gpt-oss-120b if you want to self-host, keep your data private and skip per-token fees — it's open-weight and runs on your own hardware. Choose Perceptron Mk1.5 if you want frontier capability through a managed API with zero infrastructure to run.

gpt-oss-120b vs Perceptron Mk1.5 specs

Specgpt-oss-120bPerceptron Mk1.5Winner
MakerOpenAIPerceptron–
TypeOpen-weightProprietarygpt-oss-120b
Context window131K tokens37K tokensgpt-oss-120b
Input price$0.15/M · free self-host$0.15/M= Tie
Output price$0.6/M · free self-host$1.5/Mgpt-oss-120b
Vision / multimodalNoYesPEPerceptron Mk1.5
Tool / function callingYesYes= Tie
Self-hostableYesNo (API only)gpt-oss-120b
LicenseApache 2.0Proprietarygpt-oss-120b

Price gap & when to choose each

2.5×cheaper per output token

gpt-oss-120b is ~2.5× cheaper than Perceptron Mk1.5 on output tokens ($0.6 vs $1.5 per M tokens).

Choose gpt-oss-120b if…
  • You want to self-host or run on your cloud
  • You need the longer 131K context window
  • You prioritize data privacy & control
  • You want the lowest operating costs
  • You are building open or reproducible AI
PEChoose Perceptron Mk1.5 if…
  • You want frontier performance through a managed API
  • You value reliability & ecosystem
  • You don't want to manage infrastructure

Feature comparison

Capabilitygpt-oss-120bPerceptron Mk1.5
Open weights (downloadable)✓✗
Self-hostable✓✗
Runs fully offline✓✗
Vision / multimodal✗✓
Tool / function calling✓✓
1M+ context window✗✗

Benchmarks: gpt-oss-120b vs Perceptron Mk1.5

Independent benchmark scores measured by Artificial Analysis. Higher is better (except latency).

gpt-oss-120b
Perceptron Mk1.5
Intelligence index
11.6
–
Coding index
30.4
–
Math index
93.4
–
GPQA
78.2%
–
MMLU-Pro
80.8%
–
Humanity's Last Exam
19.6%
–
Long Context Reasoning
52%
–
LiveCodeBench
87.8%
–
SciCode
34%
–
AIME 2025
93.4%
–
IFBench
69%
–
τ²-Bench
65.8%
–
τ-Bench Banking
12.8%
–
Terminal-Bench
26.2%
–
Terminal-Bench Hard
23.5%
–
Speed
221.5 tok/s
–
Latency
0.5s
–
Intelligence per $
44.3
–

Benchmark data by Artificial Analysis.

How gpt-oss-120b and Perceptron Mk1.5 score

🏆 Best value & openness: gpt-oss-120b (4.4 vs 2.9 / 5)
Criteriongpt-oss-120bPerceptron Mk1.5
Cost-efficiency5.04.5
Context window3.52.5
Openness5.01.5
Self-hosting5.01.0
Multimodality3.55.0

Scores come from live data — output price (cost), context length, open vs closed weights (openness & self-hosting) and vision/tool support (multimodality). Raw task quality isn't scored here; it depends on your benchmark — see the verdict.

What each model is

gpt-oss-120b Open

OpenAI · Open-weight

gpt-oss-120b is an open-weight, 117B-parameter Mixture-of-Experts (MoE) language model from OpenAI designed for high-reasoning, agentic, and general-purpose production use cases. It activates 5.1B parameters per forward pass and is optimize

Perceptron Mk1.5 Paid

Perceptron · Proprietary

Perceptron Mk1.5 is Perceptron's embodied reasoning model for physical agents. It accepts text, image, video, and audio input, and answers with text plus optional structured annotations: points, boxes, polygons, tracks,...

Other models in these families

These variants are tracked but not compared here — one page per family keeps the comparison readable.

Other variants tracked
gpt-oss-120b (batch)gpt-oss-20b (batch)gpt-oss-20bgpt-oss-safeguard-20b

Frequently asked questions

Is gpt-oss-120b as good as Perceptron Mk1.5?

gpt-oss-120b is open-weight and competitive on many tasks, but Perceptron Mk1.5 may still lead on the hardest reasoning and agentic work. The gap keeps narrowing — benchmark both on your actual use case before deciding.

Can I run gpt-oss-120b locally?

Yes. gpt-oss-120b has open weights, so you can self-host it on your own GPUs or run it via a low-cost API. Perceptron Mk1.5 is API-only and cannot be self-hosted.

How much cheaper is gpt-oss-120b?

gpt-oss-120b costs $0.6/M output vs $1.5/M for Perceptron Mk1.5 — roughly 3x cheaper via API, and free if you self-host.

gpt-oss-120b vs Perceptron Mk1.5 — which should I pick in 2026?

Choose gpt-oss-120b if you want to self-host, keep your data private and skip per-token fees — it's open-weight and runs on your own hardware. Choose Perceptron Mk1.5 if you want frontier capability through a managed API with zero infrastructure to run.

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