Choose DeepSeek V4 Flash if
- ✓ Your workload is text-only
- ✓ You send far more input than you expect back — classification, extraction, retrieval, log triage
- ✓ You want the lowest input price in the snapshot at $0.04 per million
Head to head · OpenRouter
DeepSeek V4 Flash vs Z.ai GLM 5.3 Flash
GLM 5.3 Flash adds vision and video input at $0.15 in / $0.50 out per million. DeepSeek V4 Flash is text-only, with the cheaper input of the two ($0.04) and the dearer output ($0.64). Both declare the same 1.31M-token window, so the window is not the tiebreaker it looks like.
Quick verdict
Since the 2026-09-22 repricing this is a read-versus-write decision rather than a cheaper-versus-dearer one. DeepSeek V4 Flash wins on anything that reads a lot and writes a little; GLM 5.3 Flash wins on mixed-media input and on generation.
Side-by-side comparison
| Field | DeepSeek V4 Flash | Z.ai GLM 5.3 Flash |
|---|---|---|
| Provider | DeepSeek | Z.ai |
| Context window | 1.05M tokens | 1.05M tokens |
| Input / 1M | $0.007 | $0.150 |
| Output / 1M | $1.28 | $0.500 |
| Modalities | Text | Text, Vision, Video |
| Best for | Budget, Long Context | Budget, Long Context, Multimodal |
Source
openrouter.ai/api/v1/models Verified 2026-10-16 Cost estimates
| Workload | Input | Output | DeepSeek V4 Flash | Z.ai GLM 5.3 Flash |
|---|---|---|---|---|
| Quick test | 20,000 | 5,000 | $0.007 | $0.005 |
| Product chat month | 500,000 | 125,000 | $0.163 | $0.138 |
| Document batch | 5,000,000 | 1,000,000 | $1.31 | $1.25 |
Estimates use list input/output prices and exclude cache discounts, provider surcharges and tool fees.
Choose Z.ai GLM 5.3 Flash if
- ✓ You need image or video input
- ✓ The job writes a lot: GLM's output costs $0.50 against DeepSeek's $0.64
- ✓ You want one model for mixed-media extraction across a 1.31M-token window
FAQ
Is DeepSeek V4 Flash cheaper than Z.ai GLM 5.3 Flash?
DeepSeek V4 Flash costs $0.007 input and $1.28 output per 1M tokens. Z.ai GLM 5.3 Flash costs $0.150 input and $0.500 output per 1M tokens.
Which model has the larger context window?
DeepSeek V4 Flash offers 1.05M tokens; Z.ai GLM 5.3 Flash offers 1.05M tokens. Provider-specific limits can vary by route.
Which one should I choose?
Since the 2026-09-22 repricing this is a read-versus-write decision rather than a cheaper-versus-dearer one. DeepSeek V4 Flash wins on anything that reads a lot and writes a little; GLM 5.3 Flash wins on mixed-media input and on generation.
DeepSeek V4 Flash details Z.ai GLM 5.3 Flash details Estimate monthly cost
Pricing and context data are based on a 2026-10-16 snapshot. Provider limits and pricing can change; verify on OpenRouter before production.