DeepSeek V3 vs DeepSeek V3.1 Terminus

DeepSeek V3 at $0.296 in and $1.18 out and DeepSeek V3.1 Terminus at $0.310 in and $1.15 out — per million tokens, from the same wallet.

DeepSeek V3

DeepSeek

0.24¢

for a client proposal

$0.296 in · $1.18 out / 1M

128K context · released December 2024

Full page →

DeepSeek V3.1 Terminus

DeepSeek

0.25¢

for a client proposal

$0.310 in · $1.15 out / 1M

131K context · released September 2025

Full page →

Asking all both at once — identical prompt, identical context — costs about 0.49¢ for a typical client proposal.

At a glance

Cheapest input: DeepSeek V3 at $0.296 per million tokens.
Cheapest output: DeepSeek V3.1 Terminus at $1.15 per million tokens.
Largest context: DeepSeek V3.1 Terminus at 131K tokens — about 190 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

DeepSeek V3

0.12¢

DeepSeek V3.1 Terminus

0.12¢

Draft a client proposal from notes

5K in · 800 out

DeepSeek V3

0.24¢

DeepSeek V3.1 Terminus

0.25¢

Context-heavy session (Alyph workspace)

155K in · 4K out

DeepSeek V3

needs 155K ctx

DeepSeek V3.1 Terminus

needs 155K ctx

Analyze a 50-page legal contract

35K in · 1K out

DeepSeek V3

1.2¢

DeepSeek V3.1 Terminus

1.2¢

Large architecture refactor

250K in · 3K out

DeepSeek V3

needs 250K ctx

DeepSeek V3.1 Terminus

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

DeepSeek V3

DeepSeek V3.1 Terminus

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

Pricing

DeepSeek V3

DeepSeek V3.1 Terminus

Input / 1M tokens

$0.296

$0.310

Output / 1M tokens

$1.18

$1.15

Cached input / 1M

—

$0.155

Specs

DeepSeek V3

DeepSeek V3.1 Terminus

Provider

DeepSeek

Released

December 2024

September 2025

Context window

128K

131K

Max output

16K

33K

Input

Text

Output

Text

Reasoning

Answers directly

Shows its thinking

Knowledge cutoff

2024-07-31

2025-03-31

Try it with real numbers

2K tokens in · 500 tokens out.

DeepSeek V3

DeepSeek

0.12¢

for this task

50% input · 50% output

Full pricing →

DeepSeek V3.1 Terminus

DeepSeek

0.12¢

for this task

52% input · 48% output

Full pricing →

All 2, same prompt and context: 0.24¢. That is the entire cost of the comparison.

Your $5 welcome credit covers about 2,101 of these.

Which should you pick?

For long documents, DeepSeek V3.1 Terminus has the largest context window here — 131K tokens.

On price, DeepSeek V3 is the cheapest of the two on a typical task, at about 0.24¢.

If you want to watch the model think, DeepSeek V3.1 Terminus shows reasoning; the other answers directly.

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 →

DeepSeek V3 pricing →DeepSeek V3.1 Terminus pricing →Add Lyria 3 Clip Preview Add Grok 4.20

Questions, answered

Which is cheaper, DeepSeek V3 or DeepSeek V3.1 Terminus?

On a typical client proposal (5K tokens in, 800 out): DeepSeek V3 at 0.24¢; DeepSeek V3.1 Terminus at 0.25¢. Long prompts can change the order when long-context rates apply.

Which has the largest context window?

DeepSeek V3.1 Terminus — 131K tokens, about 190 pages.

Can I run DeepSeek V3 and DeepSeek V3.1 Terminus 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 0.49¢ for a typical task.

Ask both at once

Identical prompt, identical context, answers side by side — about 0.49¢ for a typical client proposal. Free to start, with $5 of credit.