The team behind the gateway
Synthorai is a multimodal AI gateway: one API for LLMs, image generation, and speech. We built it because at every company we worked at, the same plumbing kept getting rebuilt: provider failover, usage metering, compliance reviews. This time we built it once, as the product itself.
What we build
One OpenAI-compatible endpoint that routes to 117+ models across the major providers: chat, image, and speech. Behind it sit prompt-cache affinity (so caching discounts actually apply), metered billing designed to survive crashes, and a BYOK vault with per-model rules.
There is no platform fee and no BYOK surcharge. We earn money when you top up and use the gateway, not from fees added on top.
Who we are
We are a small engineering team with backgrounds in security and compliance. Before Synthorai, we spent years building key management, audit trails, and data-governance systems.
We have run AI workloads in production since GPT-3, and this layer of the stack is the part we know best: how tokens get metered, how caches behave across providers, and how a gateway should fail without corrupting billing.
That experience set the defaults: encryption and least privilege everywhere, no prompt retention, and billing correctness treated as a hard requirement rather than a feature.
How we work
We write up how the hard parts work, including the failure modes: how billing stays correct when a request dies mid-stream, how we audit our own cache accounting, and how prompt caching maps across providers. Where a claim can be verified, we link the evidence: Engineering blog →
Your data is not our product
By default you can only reach models whose providers do not train on your data; anything else requires an explicit opt-in, enforced per workspace. We store request metadata for billing and nothing else: no prompts, no responses. Inference runs on infrastructure outside sensitive jurisdictions.
Company
Synthorai Technology Inc. · Mountain View, CA 94043 · Founded 2026
support@synthorai.ai · dev.to/synthorai · x.com/synthoraihq