Billing & Credits

Request charges and credit holds

SilentAPI uses prepaid credits. Add credits to your account before you send paid requests. Each request charges the credits used by the service.

Credits

One credit equals $0.01 USD. This means 100 credits equals $1.00. Credits never expire.

Credits	USD Value
1	$0.01
100	$1.00
1,000	$10.00
10,000	$100.00

Token Billing

Text and multimodal models charge per token. Token counts depend on the model and input. Each model has input and output prices:

Input price: Cost per input token.
Output price: Cost per output token.

For text without caching or extra services, the cost is (input_tokens * input_price) + (output_tokens * output_price).

Example

Read current prices in credits on the Services page or Calculator. Multiply each token count by its price per token.

Input cost:  input tokens * current input price
Output cost: output tokens * current output price
Total cost:  input cost + output cost

Other Billing Units

The billing unit depends on the service:

Image generation uses image tokens or a price per image, depending on the model.
Google Cloud Vision detection services charge per call.
Crypto Price and SilentAPI lookup services charge per call.
OCR charges use pages or calls, depending on the model. Annotation options can change the page rate.
Speech services use tokens, characters, or audio minutes, depending on the model.
Music services charge per generation. Video services charge per second at the selected resolution.

Reasoning Tokens

Models with thinking can generate reasoning tokens. These tokens count toward the output charge.

API	Usage field
OpenAI Chat Completions API	`usage.completion_tokens_details.reasoning_tokens`
Responses API	`usage.output_tokens_details.reasoning_tokens`
Gemini	`usageMetadata.thoughtsTokenCount`

Set the reasoning level with reasoning_effort. See Reasoning.

Cached Input

Cached input can have a separate price. Cache writes can also have a separate price. Support depends on the model and its response usage.

SilentAPI applies the reported cache read and write token counts without charging those tokens twice. Read current rates on the Services page and Calculator.

Long Context Pricing

Some models have a higher rate for long input. SilentAPI applies that rate from 99% of the published token threshold. Read the rates and threshold on the Services page.

Checking Your Balance

Read your balance on the Dashboard. You can also request it through the API:

curl https://api.silentapi.com/v1/silentapi/balance \
  -H "Authorization: Bearer YOUR_API_KEY"

{ "success": true, "credits": 428.55 }

Cost in Responses

Successful model responses include silentapi.cost in credits. The values below are examples:

"silentapi": {
    "cost": 0.00146,
    "fallback": null
}

Response	Where to read the cost
Model response	`silentapi.cost`
Streaming response	`silentapi.cost` in the final SSE chunk before the stream closes
File tools and OCR	Top-level `cost` field
Binary response	`X-SilentAPI-Cost` header

Insufficient Credits

SilentAPI checks your available balance before a paid request starts. Existing holds reduce the credits available for new requests.

Request	Before the request	After the request
Paid model request	SilentAPI holds the estimated maximum cost. The estimate includes the selected model and eligible fallback models.	SilentAPI charges the real cost when the request completes. It releases the hold in the same operation.
Fixed-price service, such as IP lookup, email lookup, or crypto price	No hold. SilentAPI checks that the available balance covers the price.	SilentAPI charges the price when the request completes.

If the available balance cannot cover the hold, the request fails with HTTP 402. SilentAPI releases the hold if the request fails before billable usage.

Adding Credits

Add credits on the Recharge page. Read the supported cryptocurrency payment options on Payment Methods.