AI model comparison

GLM 5.3 FlashX vs Step 3.7 Flash

Side by side comparison of GLM 5.3 FlashX and Step 3.7 Flash on pricing, benchmark scores, context window, and more.

GLM-5.3-FlashX is the high-speed variant of Z.ai's GLM-5.3-Flash, a native multimodal model delivering inference speeds of up to 200 tokens/s.

Input / 1M
$0.37
Output / 1M
$1.25
Context
1.05M

Step 3.7 Flash is StepFun's latest high-efficiency multimodal Mixture-of-Experts model.

Input / 1M
$0.20
Output / 1M
$1.15
Context
262K

Comparing image generators? Compare image models

At a glance

Quick verdict

How the two models stack up on the things people ask about most.

Lower price

stepfun logo

Step 3.7 Flash

1.4x cheaper for a typical chat

Higher intelligence score

Not available

Not enough benchmark data

Larger context window

z-ai logo

GLM 5.3 FlashX

1.05M vs 262K tokens

Newer release

z-ai logo

GLM 5.3 FlashX

Released September 18, 2026

Benchmarks

Benchmark scores

Independent scores from Artificial Analysis. Higher is better.

Intelligence index

z-ai logoGLM 5.3 FlashXNot available
stepfun logoStep 3.7 FlashNot available

Coding index

z-ai logoGLM 5.3 FlashXNot available
stepfun logoStep 3.7 Flash39.6

Agentic index

z-ai logoGLM 5.3 FlashXNot available
stepfun logoStep 3.7 FlashNot available

Pricing

GLM 5.3 FlashX vs Step 3.7 Flash API pricing

Per-token API rates. Cheaper option highlighted.

Metricz-ai logoGLM 5.3 FlashXstepfun logoStep 3.7 Flash
Input tokensPer 1M tokens$0.37$0.20
Output tokensPer 1M tokens$1.25$1.15
Cached input (read)Per 1M tokens$0.08$0.04
Cache writePer 1M tokensNot availableNot available

What it costs in practice

Estimated cost per 1,000 requests at standard rates. Coding and long-document figures also show the cost when the input is already cached.

Chat message

2K in, 500 out

z-ai logoGLM 5.3 FlashX$1.37
stepfun logoStep 3.7 Flash$0.98

Coding task

30K in, 4K out

z-ai logoGLM 5.3 FlashX$16.10$7.25 cached
stepfun logoStep 3.7 Flash$10.60$5.80 cached

Long document summary

150K in, 2K out

z-ai logoGLM 5.3 FlashX$58$13.75 cached
stepfun logoStep 3.7 Flash$32.30$8.30 cached

Specs

Context window and capabilities

How much each model can read, how much it can write, and what it accepts as input.

Metricz-ai logoGLM 5.3 FlashXstepfun logoStep 3.7 Flash
Context window1.05M tokens262K tokens
Max output131K tokens230K tokens
Input typesImage, Text, VideoImage, Text, Video
Output typesTextText
Reasoning effort levelsMax, High, LowHigh, Medium, Low
Default reasoning effortMaxMedium
Release dateSeptember 18, 2026May 28, 2026

Features

Supported features

API features available for each model.

Metricz-ai logoGLM 5.3 FlashXstepfun logoStep 3.7 Flash
Tool callingSupportedSupported
Structured outputsNot supportedSupported
JSON modeSupportedSupported
ReasoningSupportedSupported
TemperatureSupportedSupported
Stop sequencesNot supportedSupported
Deterministic seedNot supportedSupported
Verbosity controlNot supportedNot supported

Our take

Step 3.7 Flash is 1.4x cheaper for a typical chat. GLM 5.3 FlashX has the larger context window (1.05M vs 262K tokens). The right pick depends on your workload, so the quickest way to settle it is to send the same prompt to both and compare.

FAQ

Frequently asked questions

Is GLM 5.3 FlashX or Step 3.7 Flash cheaper?

Step 3.7 Flash is cheaper for a typical chat (2K input tokens and 500 output tokens). Step 3.7 Flash costs $0.20 per 1M input tokens and $1.15 per 1M output tokens, while GLM 5.3 FlashX costs $0.37 per 1M input tokens and $1.25 per 1M output tokens.

Which has a bigger context window, GLM 5.3 FlashX or Step 3.7 Flash?

GLM 5.3 FlashX supports up to 1.05M tokens of context, compared with 262K for Step 3.7 Flash.

Can I use GLM 5.3 FlashX and Step 3.7 Flash at the same time?

Yes. Shortcut Chat sends one prompt to multiple models at once, so you can see GLM 5.3 FlashX and Step 3.7 Flash answer side by side and keep the better response.

z-ai logostepfun logo

Why choose? Ask both.

Send one prompt to GLM 5.3 FlashX and Step 3.7 Flash at the same time. Compare the answers side by side and keep the best one.