OpenAI or Gemini for voice translation: which to choose

Langless supports two AI providers via BYOK: OpenAI and Gemini. Both translate voice live, and you choose which to use each session. Because prices and models change often, this guide focuses on the criteria for deciding — rather than nailing down numbers that age quickly. Always confirm prices and availability in the provider’s dashboard.

Both are supported

In Langless, you can use OpenAI or Gemini with your own key (BYOK). There’s no "right" and "wrong": it’s a matter of which one fits your usage, account and budget better. You can even keep keys for both and switch between them.

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Criterion 1: cost

Both charge by usage (per audio minute/tokens) and land in the range of a few US cents per minute. The order of magnitude is similar (~US$ 0.03/min; on OpenAI, around ~US$ 0.034/min as a reference), but the exact value varies by model and changes from time to time.

• Compare at the source: check each provider’s current pricing table before deciding.
• Think about volume: for many hours a month, small per-minute differences add up.
• Remember the subscription: this per-minute cost is separate from the Langless subscription (from US$ 25/month), which unlocks the app.

Run the math for your case in how much it costs to translate a meeting with AI.

Criterion 2: translation quality

The quality of a voice translation depends on the language, the accent, the noise and the topic of the conversation. Rather than crowning a universal "winner":

• Test on your language pair. One provider may do better on your English-Spanish and another on a less common language.
• Judge latency and fluency in practice: what matters is the conversation flowing, not a lab benchmark.

Criterion 3: availability and account

• Where you already have an account: if you already use one of the services, starting there is simpler.
• Access in your region: check whether the provider and the voice model are available for your account/country.
• Limits and billing: see how easy it is to set spending limits in each dashboard.

How to decide in practice

Suggestion: start with the provider where you already have an account, generate the key (see how to get an API key) and run a few real sessions. If the quality or cost don’t please you, create a key at the other provider and compare. Since it’s BYOK, switching is simple and with no lock-in.