No-key and authenticated request paths
The API can be called without pre-registration or an API key, while still supporting authenticated requests for callers that already have credentials.
Nitro API
Freemium
Nitro API is a human translation API for AI agents and developers, usable with or without an API key. It submits translation jobs, handles payment through an MPP-based flow, and returns translations by professional native-speaker translators in 80+ languages.
What is Nitro API?
Nitro API lets software submit translation requests for professional human review and then retrieve the finished result through an API workflow. It is designed so AI agents can use the service autonomously, with support for no-auth requests and an optional API key path.
The site describes a payment-challenge flow based on MPP, where a request can return a 402 response before being retried with a payment credential. It also provides endpoints for rate checks, price estimates, translation orders, and order status polling, making the service usable as a developer-facing translation backend.
What can Nitro API do?
MPP-based payment flow
Documentation shows a payment challenge flow where the initial translation request returns 402 Payment Required, then the caller retries with a payment credential from an MPP-compatible provider.
Order-based translation retrieval
Translation jobs are created as orders that can be polled by ID until they move from queueing to in progress and then to done.
Rates and price estimation endpoints
The API includes endpoints to get current rates per 1,000 characters and to estimate price before placing an order.
Human translation in 80+ languages
Source pages describe professional native-speaker translators working across more than 80 languages, with separate language listings for many regions.
Structured format support
The product supports complex content types such as HTML, JSON, XML, and iOS strings, with a focus on preserving tags, keys, and structure during translation.
Use Cases
“AI agents ordering translations automatically”
An agent can submit text, handle the payment challenge, and poll for results without a manual dashboard step, which fits autonomous workflows.
“Product teams localizing publishable content”
The service is suited to marketing copy, product pages, and other content that needs human translation rather than machine-only output.
“Developer workflows for structured files”
Teams working with HTML, JSON, XML, or app string files can translate content while preserving the underlying structure.
“International content programs”
The language catalog and sector examples point to use across e-commerce, software, apps, games, e-learning, travel, and other multi-language publishing needs.
“Estimate-first translation planning”
Teams can check rates and calculate an estimated cost before placing orders, which helps plan translation work inside a build or publishing pipeline.
Frequently Asked Questions
Do I need an API key to use Nitro API?
No. The site says the translation API can be called with or without an API key, and the no-auth flow is designed for AI agents.
How does payment work for no-auth requests?
The documented flow starts with a POST /translate request, returns a 402 Payment Required challenge, and then the caller retries with a payment credential from an MPP-compatible provider.
What kind of translation output does Nitro provide?
The service is positioned around human translation by professional native-speaker translators rather than machine-only output.
Can Nitro translate files or structured content?
Yes. The source pages mention support for complex formats including HTML, JSON, XML, and iOS strings, with preservation of tags and structure.
Is the API charged separately from translation work?
The translation API page says there is no charge for API services and that customers pay for the translation itself. The site also describes the pricing model as pay-as-you-go with no minimum order.
Quick Facts
- Category
- Developer Tool
- Primary use
- Human translation via API
- Authentication
- Optional; no API key required for the no-auth flow
- Languages
- 80+ languages
- Workflow
- POST /translate, pay via MPP, then poll order status
- Turnaround
- About 2-24 hours
- Source domain
- nitrotranslate.com
Nitro API Traffic Analysis
Traffic data is for reference only.
- Domain Rating
- 46
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