deepseek-flash vs gpt-5.5
Fourteen priced metrics for the same 2,000-in / 300-out call, with and without provider caching, and what TokenZero's cascade would do with the pair.
At list prices as of 2026-10-26, deepseek-flash costs $0.42 per million blended tokens on a 2,000-in / 300-out call against $8.26 for gpt-5.5, 94.9% less. With the static prefix cached both drop further: $0.52 versus $12.25 per thousand calls. TokenZero routes only prompts its classifier scores simple and holds a 99.8% parity floor.
· Source: provider list prices verified in pricing table 2026-10-26; costs computed by the same code that signs TokenZero receipts
At a glance
- Cheaper per blended token
- deepseek-flash by 94.9% (computed)
- deepseek-flash blended $/1M
- $0.42 (computed)
- gpt-5.5 blended $/1M
- $8.26 (computed)
- Input $/1M
- $0.30 vs $5.00
- Output $/1M
- $1.20 vs $30.00
- Cached input $/1M
- $0.006 vs $0.500
- Cache discount
- 98% vs 90% (computed)
- Monthly at 100k calls
- $96 vs $1,900 (computed)
- Saved per 1M calls
- $18,040 (computed)
- Providers
- deepseek vs openai
- Lifecycle
- active, no retirement announced vs active, no retirement announced
- Parity floor for routing
- 99.8% (shadow-eval breaker)
deepseek-flash vs gpt-5.5: list prices and the same workload on both (USD, table 2026-10-26)
| Metric | deepseek-flash | gpt-5.5 | Delta |
|---|---|---|---|
| Provider · tier | deepseek · fast | openai · frontier | different providers |
| Input $/1M | $0.30 | $5.00 | 94% gap |
| Output $/1M | $1.20 | $30.00 | 96% gap |
| Cached input $/1M | $0.006 | $0.500 | 98% / 90% off input |
| Cache write $/1M | no surcharge | no surcharge | |
| Minimum cacheable prefix | 1024 tokens | 1024 tokens | |
| Effective blended $/1M (2,000 in / 300 out) | $0.42 | $8.26 | deepseek-flash 94.9% less |
| Per call | $0.00096 | $0.01900 | $0.01804 |
| Per month at 100k calls | $96 | $1,900 | $1,804 |
| …with the 1,500-token prefix cached | $52 | $1,225 | $1,173 |
| Long-context threshold | single tier | 272,000 tokens ($10.00 in / $45.00 out above) | |
| Processing tiers | standard only | flex 0.5x · fast 2.5x | |
| Lifecycle | active, no retirement announced | active, no retirement announced | |
| Cheaper sibling (cascade target) | — | gpt-5.4-mini | |
| TokenZero cascade recommendation | none (cascade stays within one provider; cross-provider moves only on failover) | $18,040 saved per 1M calls if every call moved; $7,216 at a 40% simple-prompt share | 99.8% parity floor, breaker on |
Use either model through TokenZero
OPENAI_BASE_URL=https://tokenzero.sh/v1
# keep your own keys; cache formatting on, routing advisory, signed receipt per callFree up to $500/month of routed spend; paid plans take 15% of verified savings with a 3x-ROI-or-$0 rule.
What is not on this page
Third-party quality scores (coding ELO, extraction accuracy, reasoning benchmarks) and per-model latency are not shown because TokenZero does not measure them; the numbers above are prices and the arithmetic on them. The latency benchmark shows what the gateway does measure.
Questions people ask
Which is cheaper, deepseek-flash or gpt-5.5?
deepseek-flash. At list prices as of 2026-10-26 it costs $0.42 per million blended tokens versus $8.26 for gpt-5.5, a 94.9% gap on a 2,000-input / 300-output call. Per month at 100,000 calls that is $96 versus $1,900.
How much does prompt caching change the deepseek-flash vs gpt-5.5 gap?
Cached input costs $0.006 on deepseek-flash and $0.500 on gpt-5.5 per million. With a 1,500-token static prefix cached, 100,000 calls cost $52 and $1,225 respectively; TokenZero's formatter places the breakpoints and sets prompt_cache_key automatically.
Can TokenZero route gpt-5.5 traffic to deepseek-flash safely?
Not automatically: cascade routing stays inside one provider so the request shape, tools and keys are unchanged. Cross-provider moves happen only on failover when you name the fallback model and key. Use the calculator to price a manual migration of the workload.
Is deepseek-flash or gpt-5.5 being retired?
deepseek-flash: active, no retirement announced. gpt-5.5: active, no retirement announced. TokenZero audits flag retired ids and the gateway warns in X-TokenZero-Warning with the provider's replacement.