QuickSilver Pro vs OpenAI
For workloads where an open-source model is quality-equivalent, QuickSilver Pro is 10-35x cheaper than OpenAI. DeepSeek V3 replaces GPT-4o at ~10x lower cost; DeepSeek R1 replaces o1 at ~35x lower cost. For vision, audio, image generation, and the Assistants API — stay on OpenAI. This page is honest about which parts of OpenAI are worth their premium and which aren't.
At a glance
| Feature | QuickSilver Pro | OpenAI |
|---|---|---|
| Catalog | 3 open-source LLMs | GPT-4, o1, o-series, DALL-E, Whisper, TTS |
| Model weights | Open (MIT / Apache) | Closed |
| Text chat cost (GPT-4o / DeepSeek V3) | $0.24 / $0.70 | $2.50 / $10.00 |
| Reasoning cost (o1 / DeepSeek R1) | $0.40 / $1.70 | $15.00 / $60.00 |
| Vision (image input) | No | Yes (GPT-4o) |
| Audio (Whisper / TTS) | No | Yes |
| Image generation (DALL-E) | No | Yes |
| Assistants API + built-in tools | No | Yes |
| OpenAI-compatible chat + tools + JSON | Yes | Yes (original) |
| Minimum top-up | $5 | $5 |
Pricing (per million tokens, USD)
Model-for-task comparison. OpenAI pricing from platform.openai.com as of April 2026.
| Task | QSP model | QSP $/M | OpenAI model | OpenAI $/M | QSP saves |
|---|---|---|---|---|---|
| General chat / coding (input) | deepseek-v3 | $0.24 | gpt-4o | $2.50 | ~90% |
| General chat / coding (output) | deepseek-v3 | $0.70 | gpt-4o | $10.00 | ~93% |
| Reasoning / math (input) | deepseek-r1 | $0.40 | o1 | $15.00 | ~97% |
| Reasoning / math (output) | deepseek-r1 | $1.70 | o1 | $60.00 | ~97% |
| Long-context RAG (input) | qwen3.5-35b | $0.13 | gpt-4o | $2.50 | ~95% |
For a reasoning-heavy workload (200k input + 2M output R1 tokens per day), the bill is $3.48 on QuickSilver Pro vs $123 on OpenAI o1 — roughly $3,600/month saved on a single workload.
Migration — two lines
The OpenAI Python / Node / Swift SDK works unchanged. Swap the base URL and API key, rename model IDs, done.
from openai import OpenAI
client = OpenAI(
# default base_url is api.openai.com/v1
api_key=os.environ["OPENAI_API_KEY"],
)
r = client.chat.completions.create(
model="gpt-4o",
messages=[{"role": "user", "content": "Hi"}],
)
from openai import OpenAI
client = OpenAI(
base_url="https://api.quicksilverpro.io/v1",
api_key=os.environ["QSP_KEY"],
)
r = client.chat.completions.create(
model="deepseek-v3",
messages=[{"role": "user", "content": "Hi"}],
)
gpt-4o, gpt-4-turbo → deepseek-v3 (general chat, coding, JSON)o1, o1-preview → deepseek-r1 (reasoning, math)gpt-4o (long context) → qwen3.5-35b (262K window, cheaper input)Honest tradeoffs
- ›Your workload is primarily text chat completions (coding assistants, structured output, RAG summarization).
- ›DeepSeek V3 or R1 benchmarks within a few points of GPT-4o / o1 on your own evals.
- ›Cost matters — especially for reasoning workloads where the 35x gap compounds into real money.
- ›You want open-weight models (auditability, no sudden deprecation, portability).
- ›Vision — image input via GPT-4o is OpenAI-exclusive.
- ›Audio — Whisper ASR, TTS voices.
- ›Image generation — DALL-E 3, gpt-image-1.
- ›Assistants API — code interpreter, file search, built-in tool execution.
- ›GPT-4 produces measurably better output on your specific task (benchmark before switching).
- ›Embeddings (text-embedding-3-small/large). QSP doesn't serve embeddings yet.
Most teams find a hybrid pattern works: OpenAI for the closed-model-only features, QuickSilver Pro for the 80% of traffic that's plain text chat. The hybrid bill is often a small fraction of the all-OpenAI bill.
FAQ
How much cheaper is QSP than OpenAI?
DeepSeek V3 vs GPT-4o: ~10x on input, ~14x on output. DeepSeek R1 vs o1: ~37x on input, ~35x on output. Same underlying task quality on most text-only benchmarks.
Can I keep using the OpenAI SDK?
Yes, unchanged. Only the base_url + api_key + model change. Streaming, tool calling, json_schema strict mode, usage accounting — all supported.
When should I stay on OpenAI?
Vision inputs, Whisper / TTS, DALL-E, the Assistants API, embeddings, and any task where GPT-4 measurably beats DeepSeek V3 on your evals. For text-only chat that passes your evals, QSP.
Can I mix OpenAI and QSP in one app?
Yes — run two OpenAI SDK instances, one per provider, and route per-request by task. Many teams do exactly this: OpenAI for vision / audio / Assistants, QSP for the 80% of traffic that's plain text. The hybrid bill is typically 10-30% of the all-OpenAI bill.
Open-source alternatives too
Try on $1 free credits
Change the base URL, swap the key, keep everything else. See the difference.
Get API Key