
OpenAI API to DeepSeek V4 Flash: When Switching Saves Money
OpenAI API vs DeepSeek V4 Flash: real bills show a 40-42x cut ($18,000 to $450/mo). July 2026 math on when the switch is worth the migration time.

OpenAI API vs DeepSeek V4 Flash: real bills show a 40-42x cut ($18,000 to $450/mo). July 2026 math on when the switch is worth the migration time.

Sonnet 5 beats Sonnet 4.6 by 13-15% through Aug 31, 2026 — then costs 30% more after the price reverts and its tokenizer keeps burning extra tokens.

GLM-5.2 costs an estimated $0.50/1M input tokens vs Claude Sonnet 4.6 at $3/1M — a 6x gap. At Heavy workload, switching recovers the 10-hour migration cost in 2.3 months.

Cursor Pro is $20/mo flat; Claude Code via API runs $6.60–$660/mo by workload. We ran the math across 3 usage tiers to find the exact crossover point.

Claude Sonnet costs $3.00/1M input tokens; Cursor Composer 2 costs $0.50/1M. Switching saves $275/mo at Heavy workload, recovering migration cost in ~1 month.