API cost decision in 10 seconds

Qwen3.5-Flash vs gpt-oss-20b

Pick gpt-oss-20b for lower cost; pick Qwen3.5-Flash only if the larger context window matters more.

Page updated:  Data confirmed:  Prices normalized to USD per 1M tokens Sample workload: 1M input + 500K output

Budget verdict

Pick gpt-oss-20b for lower cost; pick Qwen3.5-Flash only if the larger context window matters more.

On the standard 1M input plus 500K output workload, gpt-oss-20b is estimated at $0.1 vs $0.2 for Qwen3.5-Flash, saving $0.1 (48.7% lower).

Cost-first pickgpt-oss-20b
Context-first pickQwen3.5-Flash
Sample savings$0.148.7%
10x traffic gap$0.95

Qwen3.5-Flash has more context, but gpt-oss-20b saves $0.1 on the standard workload. At 10x that traffic, the same price gap is about $0.95. Use the calculator below to replace the sample workload with your own token volume.

Cost sensitivity

Workload Sensitivity

Same prices, different token mixes.

gpt-oss-20b stays cheaper across input-heavy, balanced, and output-heavy sample workloads.

Workload shapeToken mixBetter pickQwen3.5-Flashgpt-oss-20b
Input-heavy / RAG5M input + 500K outputgpt-oss-20b$0.46$0.22
Balanced workload1M input + 1M outputgpt-oss-20b$0.33$0.17
Output-heavy chatbot1M input + 5M outputgpt-oss-20b$1.36$0.73
Cheaper input gpt-oss-20b $0.065 vs $0.03 / 1M

gpt-oss-20b is $0.04 cheaper per 1M input tokens (53.8% lower; 2.17x difference).

Cheaper output gpt-oss-20b $0.26 vs $0.14 / 1M

gpt-oss-20b is $0.12 cheaper per 1M output tokens (46.2% lower; 1.86x difference).

Larger context Qwen3.5-Flash 1M vs 131.07K

Qwen3.5-Flash has 868.93K more context (7.63x larger).

Sample workload gpt-oss-20b $0.2 vs $0.1

gpt-oss-20b is $0.1 cheaper on the standard workload (48.7% lower).

Estimate your workload cost

Your Workload Cost

Prices are normalized to USD per 1M tokens.
Qwen3.5-Flash Calculating… Estimated API cost
gpt-oss-20b Calculating… Estimated API cost
Cheaper for this workload Calculating… Difference: calculating…

This estimate uses normalized public API pricing per 1M tokens. It is a planning aid, not a billing quote. Verify provider pricing, limits, and terms before production use.

Quick Decision

Verdict

gpt-oss-20b has the lower input price; gpt-oss-20b has the lower output price; Qwen3.5-Flash offers the larger context window. For the 1M input plus 500K output sample, gpt-oss-20b is cheaper for the standard workload.

For a 1M input token plus 500K output token workload, the estimated API cost is $0.2 for Qwen3.5-Flash and $0.1 for gpt-oss-20b.

Best Fit

Choose Qwen3.5-Flash when you care most about larger context window.

Choose gpt-oss-20b when you care most about lower input-token price, and lower output-token price.

Decision Notes
  • On the standard 1M input plus 500K output workload, gpt-oss-20b is estimated at $0.1 vs $0.2 for Qwen3.5-Flash, saving $0.1 (48.7% lower).
  • gpt-oss-20b is $0.1 cheaper on the standard workload (48.7% lower).
  • gpt-oss-20b is $0.04 cheaper per 1M input tokens (53.8% lower; 2.17x difference).
  • gpt-oss-20b is $0.12 cheaper per 1M output tokens (46.2% lower; 1.86x difference).
  • Qwen3.5-Flash has 868.93K more context (7.63x larger).
Head-to-Head Specs
FeatureQwen3.5-Flash
(Qwen)
gpt-oss-20b
(OpenAI)
Input Price
prompt tokens per 1M
$0.065$0.03
Completion Price
per 1M tokens
$0.26$0.14
Sample Workload Cost
1M input + 500K output
$0.2$0.1
Context Window1M131.07K
Release Date
Popularity#25#67

Use-Case Decision Matrix

Use caseBetter pickWhy
Budget-constrained productiongpt-oss-20bOn the standard 1M input plus 500K output workload, gpt-oss-20b is estimated at $0.1 vs $0.2 for Qwen3.5-Flash, saving $0.1 (48.7% lower).
High-volume input processinggpt-oss-20bLower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill.
Long responses and chatbotsgpt-oss-20bLower output-token price matters most when assistants generate many completion tokens.
RAG or long-document workQwen3.5-FlashA larger context window leaves more room for retrieved passages, conversation history, or source files.

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Provider catalogs

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Qwen catalog

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OpenAI catalog

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