gpt-oss-20b vs o1-pro

gpt-oss-20b at $0.035 in and $0.149 out and o1-pro at $172.50 in and $690.00 out — per million tokens, from the same wallet.

gpt-oss-20b

OpenAI

0.03¢

for a client proposal

$0.035 in · $0.149 out / 1M

131K context · released August 2025

Full page →

o1-pro

OpenAI

$1.41

for a client proposal

$172.50 in · $690.00 out / 1M

200K context · released March 2025

Full page →

Asking all both at once — identical prompt, identical context — costs about $1.41 for a typical client proposal.

At a glance

Cheapest input: gpt-oss-20b at $0.035 per million tokens.
Cheapest output: gpt-oss-20b at $0.149 per million tokens.
Largest context: o1-pro at 200K tokens — about 290 pages.

Cost per task

Estimated totals at the rates above. Solid bar is input, lighter bar is output.

Quick code fix

2K in · 500 out

gpt-oss-20b

0.01¢

o1-pro

$0.69

Draft a client proposal from notes

5K in · 800 out

gpt-oss-20b

0.03¢

o1-pro

$1.41

Context-heavy session (Alyph workspace)

155K in · 4K out

gpt-oss-20b

needs 155K ctx

o1-pro

$29.50

Analyze a 50-page legal contract

35K in · 1K out

gpt-oss-20b

0.14¢

o1-pro

$6.73

Large architecture refactor

250K in · 3K out

gpt-oss-20b

needs 250K ctx

o1-pro

needs 250K ctx

Solid part of each bar is input tokens, the lighter part is output. Models that don’t fit a task are marked instead of priced.

Cost vs Token Amount

Drag the slider to adjust the split between input and output workload.

80% Input20% Output

gpt-oss-20b

o1-pro

Adjust the ratio slider to change how output tokens influence the final price for equivalent workloads.

Pricing

gpt-oss-20b

o1-pro

Input / 1M tokens

$0.035

$172.50

Output / 1M tokens

$0.149

$690.00

Cached input / 1M

$0.035

—

Web search

—

1.1¢ / search

Specs

gpt-oss-20b

o1-pro

Provider

OpenAI

Released

August 2025

March 2025

Context window

131K

200K

Max output

131K

100K

Input

Text

Text, Images, and Files

Output

Text

Reasoning

Shows its thinking

Knowledge cutoff

2024-06-30

2023-10-31

Try it with real numbers

2K tokens in · 500 tokens out.

gpt-oss-20b

OpenAI

0.01¢

for this task

48% input · 52% output

Full pricing →

o1-pro

OpenAI

$0.69

for this task

50% input · 50% output

Full pricing →

All 2, same prompt and context: $0.69. That is the entire cost of the comparison.

Your $5 welcome credit covers about 7 of these.

Which should you pick?

For long documents, o1-pro has the largest context window here — 200K tokens.

On price, gpt-oss-20b is the cheapest of the two on a typical task, at about 0.03¢.

For images or files, o1-pro can read them directly; gpt-oss-20b is text-only.

Or don’t pick. Send the identical prompt to all both, read the answers side by side, and keep the winner. How to run a fair bake-off →

gpt-oss-20b pricing →o1-pro pricing →Add Lyria 3 Clip Preview Add Grok 4.20

Questions, answered

Which is cheaper, gpt-oss-20b or o1-pro?

On a typical client proposal (5K tokens in, 800 out): gpt-oss-20b at 0.03¢; o1-pro at $1.41. Long prompts can change the order when long-context rates apply.

Which has the largest context window?

o1-pro — 200K tokens, about 290 pages.

Can I run gpt-oss-20b and o1-pro side by side on Alyph?

Yes — that is what Alyph is built for: the identical prompt with identical context to all 2, answers rendered side by side, billed from one wallet. This exact combination costs about $1.41 for a typical task.

Ask both at once

Identical prompt, identical context, answers side by side — about $1.41 for a typical client proposal. Free to start, with $5 of credit.