What is OpenRouter?
OpenRouter is a model aggregator: one OpenAI-compatible API that routes each request to one of hundreds of models from 80+ providers — OpenAI, Anthropic, Google, Mistral and a long tail of open-source hosts. Instead of an account per provider, you hold one OpenRouter account and choose the model by name in the request. It is not text-only. As of September 2026 its docs describe a dedicated image API (POST /api/v1/images), an asynchronous video API (POST /api/v1/videos), text-to-speech and speech-to-text endpoints, and an Anthropic Messages-format endpoint (POST /api/v1/messages) with a Claude Code setup guide, and its pricing page lists 25+ free models (sources: openrouter.ai/docs, openrouter.ai/pricing).
How the OpenRouter API works
You send a standard OpenAI-style chat completion to OpenRouter's base URL with your OpenRouter key, setting the model field to a namespaced slug such as anthropic/claude-sonnet or openai/gpt-4o. OpenRouter forwards the call to that provider, can fall back to alternates, and returns the OpenAI-shaped response. Because it speaks the OpenAI protocol, any OpenAI SDK works by pointing base_url at it. Kunavo works the same way — the difference is the catalog and what sits behind it.
OpenRouter pricing, and how Kunavo compares
OpenRouter passes the provider's per-token price through with no markup on inference and charges a fee when you buy credits instead: 5.5% with a $0.80 minimum by card, 5% for USDC crypto, 8% on its Business plan. Bringing your own provider keys has separate terms — on pay-as-you-go the first $25,000 of list-price inference a month carries no BYOK fee, then 5% — and its free models are capped at 50 requests a day, or 1,000 once you have bought at least $10 of credits (sources: openrouter.ai/docs/faq and openrouter.ai/pricing, as of September 2026). Kunavo takes the other side of the trade: top-ups are credited in full, and most models are listed under the provider's official rate — Claude Sonnet 4.6 at $1.20/$6.00 per 1M tokens vs Anthropic's $3.00/$15.00, Gemini 2.5 Flash at $0.09/$0.75 vs Google's $0.30/$2.50, while Claude Sonnet 5 sits at list ($2.00/$10.00). Kunavo has no free models. The per-1M rate for every model is on the /pricing page, so the comparison is direct.
OpenRouter API key vs Kunavo API key
Both are bearer tokens in the Authorization header, and each reaches its whole platform. An OpenRouter key covers chat, the Anthropic Messages-format endpoint and the image, video and speech APIs (per its docs, as of September 2026); a Kunavo key (sk-kn-…) covers the OpenAI-compatible chat endpoint, image, video and music endpoints and the native Anthropic Messages API, drawn from one prepaid USD balance topped up through Stripe. What differs is the catalog behind the key and how the balance is funded, so moving across is a one-line base_url change plus the new key.
Where OpenRouter genuinely wins
Breadth and free inference. If your product needs the long tail of chat models — Mistral fine-tunes, Llama variants, niche community models, experimental open-source — OpenRouter's catalog of hundreds of models from 80+ providers is unmatched, and its pricing page lists 25+ free models you can call at low daily limits; Kunavo has no free models at all. It also lets you bring your own provider keys, with the first $25,000 of list-price inference a month fee-free on pay-as-you-go, and it takes USDC, which matters in regions where cards are difficult. With image, video, speech and Lyria music models of its own, multimodal alone is no longer a reason to leave (sources: openrouter.ai/pricing, openrouter.ai/docs, as of September 2026).
Where Kunavo wins
Price, on the models most products actually ship. OpenRouter bills the provider's list price plus a fee on every credit purchase; Kunavo lists most of its catalog under the provider's official rate — Claude Sonnet 4.6 60% under Anthropic's list price, Gemini 2.5 Flash 70% under Google's list price — credits top-ups in full, and publishes the per-1M-token rate for every model on /pricing (a few models, Claude Sonnet 5 among them, sit at list). Media sits on the same key and wallet: /v1/images, /v1/images/edits, /v1/video/generations and /v1/audio/music alongside chat, all OpenAI-shaped, with Suno for music — a model OpenRouter's list does not carry. Stripe checkout adds rails OpenRouter's FAQ does not mention — Apple Pay, Pix, WeChat Pay, Link — which makes self-serve onboarding work outside the US and EU. The trade-offs to weigh: Kunavo curates frontier models rather than hundreds, offers no free models or BYOK, and runs on shared upstream capacity with no contractual SLA.
How you pay: OpenRouter vs Kunavo
Both wallets are prepaid, so at signup the only question that matters is whether your money can get in. Kunavo's checkout is Stripe-native, so the list follows the buyer rather than our billing country: cards (Visa, Mastercard, Amex, JCB, UnionPay) and Apple Pay everywhere Stripe reaches, Link and Cash App Pay for one-tap repeat top-ups, Klarna and Amazon Pay, and Alipay and WeChat Pay for mainland China. Local rails appear by country — Pix in Brazil, Bancontact in Belgium, BLIK in Poland, EPS in Austria, MB WAY in Portugal — with Stripe converting the dollar amount into local currency on the checkout page, so a Brazilian buyer scans a Pix QR code for an amount in reais instead of hunting for a card cleared for international purchases. OpenRouter's own FAQ answers it plainly: all major credit cards, Alipay, and cryptocurrency in USDC, with PayPal described as something they are still working on, and its pricing page adds bank transfers (as of September 2026). That covers a developer holding a card, crypto or a bank account. Neither page mentions Pix or Apple Pay, and that is the gap Kunavo's checkout fills: the buyer in São Paulo without a card cleared for international purchases, or the one who would rather confirm a top-up with Face ID than type sixteen digits.
Migrating from OpenRouter
Both APIs speak the OpenAI chat-completions protocol, so the port is two lines, not a rewrite. Point base_url at https://api.kunavo.com/v1, swap your sk-or- key for a Kunavo sk-kn- key created at /app/keys, and your existing OpenAI SDK code runs unchanged — same request shape, same streaming, same tool-call format. The one thing to check is model ids: OpenRouter namespaces them by vendor (anthropic/claude-sonnet-4.6), Kunavo uses the bare id (claude-sonnet-4-6), so a find-and-replace over your model constants finishes the job. Nothing else in your stack moves: no SDK swap, no response parsing changes, no webhook rework. Run both side by side on the same code path if you want — two clients differing only in base_url — and cut over once you've compared latency and cost on your own traffic.
The honest takeaways
If you've standardized on OpenRouter and lean on its breadth, its free models or BYOK, there's no strong forcing function to switch — your existing OpenAI SDK code is portable to Kunavo (one base_url change), so you can keep both in your back pocket and move traffic when the price gap is worth the integration time. If most of your spend sits on frontier models Kunavo lists under official rates, you want Suno next to chat on one bill, or you serve customers paying with local rails like Pix or WeChat Pay, Kunavo is the simpler stack. Either way, the test is small: a $10 top-up and one base_url change get you evaluating in minutes.