# PubChem Compound Search & Lookup — Official NIH API (`quartz_apple_dnx/pubchem-compound-search-api`) Actor

Look up compounds by name or PubChem CID and return core chemical properties from the official NIH PubChem PUG REST API.

- **URL**: https://apify.com/quartz_apple_dnx/pubchem-compound-search-api.md
- **Developed by:** [Piven Core](https://apify.com/quartz_apple_dnx) (community)
- **Categories:** Developer tools, Business
- **Stats:** 2 total users, 1 monthly users, 100.0% runs succeeded, 0 bookmarks
- **User rating**: No ratings yet

## Pricing

$0.25 / 1,000 resolved pubchem compounds

This Actor is paid per event. You are not charged for the Apify platform usage, but only a fixed price for specific events.

Learn more: https://docs.apify.com/actors/running/actors-in-store.md#pay-per-event

## What's an Apify Actor?

An Actor is a serverless cloud program that runs on the Apify platform. It has two run modes.
In Batch mode, an Actor accepts a well-defined JSON input, performs an action which can take anything from a few seconds to a few hours,
and optionally produces a well-defined JSON output, datasets with results, or files in key-value store.
In Standby mode, an Actor provides a web server which can be used as a website, API, or an MCP server.

Apify vocabulary and the platform model are defined once, in the agent quickstart at https://apify.com/agents.md.

## How to integrate an Actor?

If asked about integration, you help developers integrate Actors into their projects.
You adapt to their stack and deliver integrations that are safe, well-documented, and production-ready.

Do not guess an integration path. Every one of them is in the agent quickstart at https://apify.com/agents.md: the Apify MCP server, Agent Skills with the Apify CLI, the JavaScript and Python clients, the REST API, and the account-free path for an agent with no human to sign in. It also carries the rule on stating cost before the first paid run.

For examples already wired to this Actor's own input schema, see the [API](#api) section below.

Each client library has reference documentation the quickstart does not restate: [JavaScript/TypeScript](https://docs.apify.com/api/client/js/docs.md) (`npm install apify-client`) and [Python](https://docs.apify.com/api/client/python/docs.md) (`pip install apify-client`).

# README

## PubChem Compound Search & Lookup — Official NIH API

Resolve compound names or PubChem CIDs against the official NIH PubChem PUG REST API and export compact chemical-property rows.

Use it for **compound lookup, chemistry data normalization, research datasets, identifier resolution, chemical informatics, and automated PubChem workflows**.

**Independent tool. Not affiliated with or endorsed by NIH, NCBI, or PubChem. Not medical, toxicology, laboratory, or regulatory advice.**

### Common use cases

- Resolve common compound names to PubChem CIDs
- Look up known CIDs and retrieve standard chemical properties
- Normalize compound identifiers for research datasets
- Collect molecular formula, mass, SMILES, InChI, and related properties
- Feed structured PubChem records into downstream research workflows

### What you get

Successful rows include PubChem CID/title, molecular formula/weight, SMILES, InChI/InChIKey, IUPAC name, XLogP, exact and monoisotopic mass, TPSA, complexity, hydrogen-bond counts, rotatable-bond count, heavy-atom count, and formal charge when returned.

### Try it

```json
{
  "queries": ["aspirin", "caffeine", "2244"],
  "queryType": "auto"
}
```

### Source

PubChem PUG REST: `https://pubchem.ncbi.nlm.nih.gov/rest/pug`

PubChem asks automated clients to stay at or below 5 requests per second and may dynamically throttle traffic. This Actor globally spaces upstream calls to about 4 requests/second and retries transient 429/5xx/503 failures with backoff.

### Important limitations

Not-found inputs emit diagnostic rows. If every input is unresolved, the Actor also emits a non-billed zero-result summary.

This Actor reports source chemical data. It does not determine medical suitability, toxicity, laboratory safety, regulatory status, or appropriate handling/use of a compound.

### Pricing

Only successfully resolved compound rows are billed. Not-found diagnostic rows, zero-result summaries, and budget-limit summaries are not billed.

Candidate target: **$0.25 per 1,000 resolved compound rows**, subject to live economics and the strengthened release gate.

### About Piven Core

Built and maintained by **Piven Core** — focused data APIs and automation utilities for reliable, production-ready workflows.

Learn more: https://pivencore.com

# Actor input Schema

## `queries` (type: `array`):

1 to 100 compound names or PubChem CIDs. Examples: aspirin, caffeine, 2244. Input order is preserved.

## `queryType` (type: `string`):

auto treats all-digit inputs as CIDs and other inputs as compound names.

## `maxConcurrency` (type: `integer`):

PubChem asks clients to stay at or below 5 requests/second. This Actor also rate-limits globally.

## `maxRequestRetries` (type: `integer`):

Retries transient PubChem/server/network errors with backoff.

## Actor input object example

```json
{
  "queries": [
    "aspirin",
    "caffeine",
    "2244"
  ],
  "queryType": "auto",
  "maxConcurrency": 2,
  "maxRequestRetries": 2
}
```

# Actor output Schema

## `dataset` (type: `string`):

No description

# API

You can run this Actor programmatically using our API. Below are code examples in JavaScript, Python, and CLI, as well as the OpenAPI specification and MCP server setup.

## JavaScript example

```javascript
import { ApifyClient } from 'apify-client';

// Initialize the ApifyClient with your Apify API token
// Replace the '<YOUR_API_TOKEN>' with your token
const client = new ApifyClient({
    token: '<YOUR_API_TOKEN>',
});

// Prepare Actor input
const input = {
    "queries": [
        "aspirin",
        "caffeine",
        "2244"
    ]
};

// Run the Actor and wait for it to finish
const run = await client.actor("quartz_apple_dnx/pubchem-compound-search-api").call(input);

// Fetch and print Actor results from the run's dataset (if any)
console.log('Results from dataset');
console.log(`💾 Check your data here: https://console.apify.com/storage/datasets/${run.defaultDatasetId}`);
const { items } = await client.dataset(run.defaultDatasetId).listItems();
items.forEach((item) => {
    console.dir(item);
});

// 📚 Want to learn more 📖? Go to → https://docs.apify.com/api/client/js/docs

```

## Python example

```python
from apify_client import ApifyClient

# Initialize the ApifyClient with your Apify API token
# Replace '<YOUR_API_TOKEN>' with your token.
client = ApifyClient("<YOUR_API_TOKEN>")

# Prepare the Actor input
run_input = { "queries": [
        "aspirin",
        "caffeine",
        "2244",
    ] }

# Run the Actor and wait for it to finish
run = client.actor("quartz_apple_dnx/pubchem-compound-search-api").call(run_input=run_input)

# Fetch and print Actor results from the run's dataset (if there are any)
print(f"💾 Check your data here: https://console.apify.com/storage/datasets/{run.default_dataset_id}")
for item in client.dataset(run.default_dataset_id).iterate_items():
    print(item)

# 📚 Want to learn more 📖? Go to → https://docs.apify.com/api/client/python/docs/quick-start

```

## CLI example

```bash
echo '{
  "queries": [
    "aspirin",
    "caffeine",
    "2244"
  ]
}' |
apify call quartz_apple_dnx/pubchem-compound-search-api --silent --output-dataset

```

## MCP server setup

```json
{
    "mcpServers": {
        "apify": {
            "type": "http",
            "url": "https://mcp.apify.com/?tools=fetch-actor-details,quartz_apple_dnx/pubchem-compound-search-api"
        }
    }
}
```

The hosted server signs you in with OAuth on first connect, so no API token belongs in this config. Clients without OAuth support can send an `Authorization: Bearer <APIFY_API_TOKEN>` header instead, using a token from API & Integrations in Apify Console (https://console.apify.com/settings/integrations).

## OpenAPI specification

Download the OpenAPI definition: https://api.apify.com/v2/actors/mpTxwbbRlB5zcZcT3/builds/0dU5NXU0jNfKDiAks/openapi.json