Model comparison

DeepSeek V4 Flash vs Laguna S 2.1

Data verified July 21, 2026

Head-to-head evidence from 4 shared benchmark results across 2 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.

DeepSeek V4 Flash

DeepSeek

58.88/100

No comparison

Laguna S 2.1

Poolside

N/A

1 category wins1 category wins

Public leaderboard positions: DeepSeek V4 Flash #61 (Estimated); Laguna S 2.1 unranked (Not scored). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.

Evidence parity. DeepSeek V4 Flash and Laguna S 2.1 share 4 comparable benchmark results. 2 of 8 categories are comparable. 18 results are unique to DeepSeek V4 Flash; 2 to Laguna S 2.1.

Updated July 21, 2026

Shared results: 4
DeepSeek V4 Flash only: 18
Laguna S 2.1 only: 2
Comparable categories: 2 / 8

Treat this as a split decision. DeepSeek V4 Flash makes more sense if coding is the priority or you would rather avoid the extra latency and token burn of a reasoning model; Laguna S 2.1 is the better fit if agentic is the priority or you want the cheaper token bill.

Confidence note. This is a partial-evidence comparison with 4 shared benchmark results across 2 evidence categories; 2 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.

Why this result

DeepSeek V4 Flash and Laguna S 2.1 finish on the same BenchAlign overall score, so this is less about a single winner and more about where the edge shows up. The BenchAlign headline says tie; the benchmark table is where the real choice happens.

DeepSeek V4 Flash is also the more expensive model on tokens at $0.14 input / $0.28 output per 1M tokens, versus $0.10 input / $0.20 output per 1M tokens for Laguna S 2.1. Laguna S 2.1 is the reasoning model in the pair, while DeepSeek V4 Flash is not. That usually helps on harder chain-of-thought-heavy tests, but it can also mean more latency and more token spend in real use.

Category breakdown

Exact category averages are shown below. Not measured means BenchLM does not have enough sourced public coverage for that model and category.

Category scores and score margins for DeepSeek V4 Flash and Laguna S 2.1
Category	DeepSeek V4 Flash	Δ	Laguna S 2.1
Agentic	DeepSeek V4 Flash49.1	Margin→ 21.1	Laguna S 2.170.2
Coding	DeepSeek V4 Flash64.2	Margin← 4.8	Laguna S 2.159.4
Knowledge	DeepSeek V4 Flash38.8	MarginNo overlap	Laguna S 2.1Not measured
Math	DeepSeek V4 Flash40.8	MarginNo overlap	Laguna S 2.1Not measured

Decisive benchmark drivers

The largest measured benchmark gaps in this matchup, with exact reported values.

A · DeepSeek V4 FlashB · Laguna S 2.1

Terminal-Bench 2.0
Agentic
Source ↗
A 49.1%B 70.2%
Winner: Laguna S 2.1Δ 21.1
Terminal-Bench 2.0: DeepSeek V4 Flash scored 49.1%; Laguna S 2.1 scored 70.2%. Laguna S 2.1 wins this benchmark.
SWE-bench Pro
Coding
Source ↗
A 49.1%B 59.4%
Winner: Laguna S 2.1Δ 10.3
SWE-bench Pro: DeepSeek V4 Flash scored 49.1%; Laguna S 2.1 scored 59.4%. Laguna S 2.1 wins this benchmark.

Operational comparison

Runtime and commercial metrics are compared only when both models have a complete sourced value.

Metric	DeepSeek V4 Flash	Laguna S 2.1	Comparison
Input / output priceUSD per 1M tokens	DeepSeek V4 Flash$0.14 input / $0.28 output	Laguna S 2.1$0.1 input / $0.2 output	Laguna S 2.1 has the lower combined listed price.
Generation speedtokens per second	DeepSeek V4 FlashNot available	Laguna S 2.1Not available	A complete speed comparison is not available.
First-answer latencyseconds to first token	DeepSeek V4 FlashNot available	Laguna S 2.1Not available	A complete latency comparison is not available.
Context windowmaximum listed tokens	DeepSeek V4 Flash1M	Laguna S 2.11M	Listed context windows are equal.

Benchmark Deep Dive

AgenticLaguna S 2.1 wins

6 benchmarks

Benchmark	DeepSeek V4 Flash	Laguna S 2.1	Result
Terminal-Bench 2.0Source	49.1%	70.2%	Laguna S 2.1 leads
MCP AtlasSource	64%	—	Not comparable
ToolathlonSource	40.7%	—	Not comparable
Claw-EvalSource	57.8%	—	Not comparable
Gert LabsSource	54.35%	—	Not comparable
Toolathlon-VerifiedSource	—	49.7%	Not comparable

CodingDeepSeek V4 Flash wins

5 benchmarks

Benchmark	DeepSeek V4 Flash	Laguna S 2.1	Result
SWE-bench VerifiedSource	73.7%	—	Not comparable
SWE-bench ProSource	49.1%	59.4%	Laguna S 2.1 leads
SWE MultilingualSource	69.7%	78.5%	Laguna S 2.1 leads
Terminal-Bench 2.0Source	49.1%	70.2%	Laguna S 2.1 leads
deepSweSource	—	40.4%	Not comparable

Reasoning

2 benchmarks

Benchmark	DeepSeek V4 Flash	Laguna S 2.1	Result
MRCR 1MSource	37.5%	—	Not comparable
CorpusQA 1MSource	15.5%	—	Not comparable

Knowledge

6 benchmarks

Benchmark	DeepSeek V4 Flash	Laguna S 2.1	Result
MMLU-ProSource	83%	—	Not comparable
SimpleQASource	23.1%	—	Not comparable
Chinese-SimpleQASource	71.5%	—	Not comparable
GPQASource	71.2%	—	Not comparable
GPQA-DSource	71.2%	—	Not comparable
HLESource	8.1%	—	Not comparable

Math

4 benchmarks

Benchmark	DeepSeek V4 Flash	Laguna S 2.1	Result
HMMT Feb 2026Source	40.8%	—	Not comparable
IMOAnswerBenchSource	41.9%	—	Not comparable
ApexSource	1.0%	—	Not comparable
Apex ShortlistSource	9.3%	—	Not comparable

Multimodal

1 benchmarks

Benchmark	DeepSeek V4 Flash	Laguna S 2.1	Result
Design Arena WebsiteSource	1238	—	Not comparable

Frequently Asked Questions (3)

Which is better, DeepSeek V4 Flash or Laguna S 2.1?

DeepSeek V4 Flash and Laguna S 2.1 are tied on the BenchAlign overall score, so the right pick depends on which category matters most for your use case.

Which is better for coding, DeepSeek V4 Flash or Laguna S 2.1?

DeepSeek V4 Flash has the edge for coding in this comparison, averaging 64.2 versus 59.4. Inside this category, Terminal-Bench 2.0 is the benchmark that creates the most daylight between them.

Which is better for agentic tasks, DeepSeek V4 Flash or Laguna S 2.1?

Laguna S 2.1 has the edge for agentic tasks in this comparison, averaging 70.2 versus 49.1. Inside this category, Terminal-Bench 2.0 is the benchmark that creates the most daylight between them.

Related Comparisons

Explore More

DeepSeek Compare Pricing Methodology Find Your Best LLM Overall Rankings

Last updated: July 21, 2026

Choose a model with this week’s evidence

Join 2,000+ readers for ranking moves, pricing changes, and the claims that still need proof.

One email each week. Unsubscribe anytime.