DeepSeek V4.1 Flash vs GLM 5.3 Flash, head to head

Side A

Side B

Overall

DeepSeek V4.1 Flash is clearly better. It wins 62 of the 69 test cases where they differ.

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Task by task

A score turns orange only when that model wins clearly more of the task's test cases. Under each score, the average time per test case on the machine it ran on. DeepSeek V4.1 Flash spends 2.2× as many thinking tokens per test case.

Thinking tokensAnswer tokens

TaskADeepSeek V4.1 FlashBGLM 5.3 FlashDeepSeek V4.1 FlashGLM 5.3 Flash

Overall

643m 35s

6K2.8K

3555.5s

Agents

Runs multi-step jobs through tools, within a written policy

464m 42s

6.1K607

1037.0s

Structured Extraction

Turns logs, diffs and records into exact JSON

862m 8s

4.4K2.7K

4847.2s

Coding

Writes code and SQL that pass hidden tests

514m 55s

9.7K5.3K

541m 52s

Grounded Answers

Answers from the given documents with sources, never guesses

762m 17s

3.9K2.9K

3756.8s

Instruction Following

Applies every rule, including ones changed mid-conversation

894m 24s

7.5K2K

4340.8s

Business Logic

Computes billing, scheduling and pricing rules exactly

814m 1s

7K5.8K

331m 18s

Security & permissions

Ignores planted instructions, still does the allowed work

693m 3s

4.4K963

5525.2s

Diagnosis & investigation

Chooses diagnostic checks, repairs supported causes and verifies recovery

172m 8s

3.2K563

027.0s

What you'd run

The build behind each score. Orange marks the faster, smaller, cheaper or longer-context side.

SpecADeepSeek V4.1 FlashBGLM 5.3 Flash

Speed

30 tok/s

60 tok/s

Machine

Hosted

Memory at 32K

—

Context

Cost per run

$0.39

$0.19

Cost per case

$0.0026

$0.0013

Time per case

3m 35s

55.5s

Quantization

FP8

Harness

openrouter

The race

No lead changes

Each model's running score as the test cases go by. The dashed line is a perfect run.

DeepSeek V4.1 FlashGLM 5.3 Flash

Every test case

153 test cases

Each square is one test case, colored by the model that scored higher.

Agents80

Structured Extraction91

Coding74

Grounded Answers101

Instruction Following120

Business Logic100

Security & permissions51

Diagnosis & investigation10

62 won by DeepSeek V4.1 Flash7 won by GLM 5.3 Flash84 tied