The rate cards side by side
| DeepSeek V4.1 Flash | GPT-6.1 Sol | |
|---|---|---|
| Input / 1M | $0.15 off-peak / $0.30 peak | $2.00 |
| Output / 1M | $0.60 off-peak / $1.20 peak | $10.00 |
| Cached input / 1M | $0.003 / $0.006 (automatic) | $0.10 (5%) |
| Batch / 1M | No batch tier; off-peak is the discount | $1.00 / $5.00 |
| Long-context rule | Flat across 1M window | $4/$15 past 272K tokens |
| Context window | 1M tokens | 1M tokens |
DeepSeek's rates are verified on DeepSeek's official API pricing page; Sol's on OpenAI's pricing page. Off-peak, Flash is ~13× cheaper on input and ~17× on output. Even at peak ($0.30/$1.20), it is roughly 7×/8× cheaper than Sol's standard rate — and cheaper than Sol's batch rate.
Cost per task: the gap in dollars
GPT-6.1 Sol (standard): 100 × $2 + 20 × $10 = $400
GPT-6.1 Sol (batch): $200
DeepSeek Flash (off-peak): 100 × $0.15 + 20 × $0.60 = $27
DeepSeek Flash (peak): $54
The gap is so large that the interesting question is not "which is cheaper" but "what would make Sol worth 15×?" The honest answers: tasks where Flash measurably fails, enterprise requirements only OpenAI meets, or latency/availability guarantees. Everything else belongs on Flash.
Quality: what we can and cannot say
JetAI makes no measured quality claim here — we publish no in-house benchmark scores, and we do not invent benchmarks. What is attributable: DeepSeek's own model-card numbers, as reported by third-party technical analyses, place V4.1 Flash above the old V4 Pro on agent and coding work but not on knowledge tasks — vendor-published figures, not independent verification. The practical move is the one the price gap demands: default to Flash, escalate the calls that fail, and let your own evals — not a vendor chart — decide the split.
Which to pick
- Pick DeepSeek V4.1 Flash for bulk classification, extraction, summarization, RAG pipelines, and any high-volume workload you can schedule off-peak. It is the cheapest capable API on the rate cards we track.
- Pick GPT-6.1 Sol when you need OpenAI's ecosystem (fine-tuning-adjacent tooling, enterprise agreements, specific integrations), batch processing with 24h SLAs, or when your evals show Flash failing on your task class.
- Pick both: Flash as the default route, Sol as the escalation tier. At a 15× price gap, the router pays for itself with the first escalated batch.
Deep dives: DeepSeek pricing, GPT-6.1 Sol pricing lanes. Model the peak-hour math with the bill estimator.
Quick answers
Is DeepSeek cheaper than GPT-6.1 Sol?
Dramatically. Verified October 2026: DeepSeek V4.1 Flash costs $0.15/$0.60 per million tokens off-peak against GPT-6.1 Sol's $2/$10 — roughly 13x cheaper on input and 17x on output. Even at DeepSeek's peak rates ($0.30/$1.20), it undercuts Sol's standard rates and matches its batch tier on output.
What is the catch with DeepSeek pricing?
Peak-hour billing: rates double during 01:00–04:00 and 06:00–10:00 UTC, Monday to Friday, excluding Chinese public holidays — schedule bulk work outside those windows. Also verify quality on your own tasks before migrating: the price gap only matters if the cheaper model actually handles your workload to your bar.
Does DeepSeek V4.1 Flash have a batch API?
No batch tier exists on the current rate card. DeepSeek's discount mechanism is different: off-peak pricing halves the peak rates for most of the week, and automatic prompt caching drops repeated input to $0.003/1M — a deeper discount than any batch tier on this page, with no 24-hour wait attached.
Which is better for coding, DeepSeek V4.1 Flash or GPT-6.1 Sol?
We make no measured quality claim for either model — JetAI publishes no in-house benchmark scores. DeepSeek's vendor-published model-card numbers place V4.1 Flash above the old V4 Pro on agent and coding work, but those are vendor figures, not independent measurement. Test both on your own tasks and compare cost per completed task.