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---
title: "PMC (PubMed Central)"
task: ""
lineage_type: import
upstream_source: https://github.com/K-Dense-AI/scientific-agent-skills/blob/9c9bd2e9/skills/paper-lookup/references/pmc.md
upstream_sha: 9c9bd2e9
imported_at: 2026-06-27
prompt_class: prompt
upstream_changes: accepted
author: upstream
validated: false
---
# PMC (PubMed Central)
PMC is a **full-text archive** of biomedical and life sciences articles. It is separate from PubMed -- PubMed has citations/abstracts, PMC has full text. Not all PubMed articles are in PMC, and vice versa.
## E-utilities for PMC
### Base URL
```
https://eutils.ncbi.nlm.nih.gov/entrez/eutils/
```
Same E-utilities as PubMed, but with `db=pmc`.
### eSearch -- Search PMC
```
GET /esearch.fcgi?db=pmc&term={query}&retmode=json
```
Same parameters as PubMed eSearch. Returns PMC UIDs (numeric, e.g., `13033346`). You need to prepend "PMC" to get a PMCID (e.g., `PMC13033346`).
### eFetch -- Get Full Text XML
```
GET /efetch.fcgi?db=pmc&id={pmcid}&retmode=xml
```
| rettype | retmode | Returns |
|---------|---------|---------|
| *(omit)* | `xml` | **Full text JATS XML** (body, figures, references) |
| `medline` | `text` | MEDLINE format |
**Example:**
```
https://eutils.ncbi.nlm.nih.gov/entrez/eutils/efetch.fcgi?db=pmc&id=7029759&retmode=xml
```
The XML uses JATS (Journal Article Tag Suite) format:
- `<front>` -- journal metadata, article metadata, author info
- `<body>` -- full article text with `<sec>` sections, `<p>` paragraphs, `<fig>` figures
- `<back>` -- `<ref-list>` with all references
Pass numeric IDs only (not "PMC7029759", just "7029759").
## BioC API -- Structured Full Text
An alternative way to get full text in a structured passage format.
### Base URL
```
https://www.ncbi.nlm.nih.gov/research/bionlp/RESTful/pmcoa.cgi/
```
### Endpoint
```
GET /BioC_{format}/{id}/{encoding}
```
| Parameter | Values |
|-----------|--------|
| `format` | `json` or `xml` |
| `id` | PMID (e.g., `17299597`) or PMCID (e.g., `PMC7029759`) |
| `encoding` | `unicode` or `ascii` |
**Example:**
```
https://www.ncbi.nlm.nih.gov/research/bionlp/RESTful/pmcoa.cgi/BioC_json/PMC7029759/unicode
```
**Response structure (JSON):**
```json
{
"source": "PMC",
"documents": [{
"id": "PMC7029759",
"infons": {"license": "...", "doi": "..."},
"passages": [
{
"offset": 0,
"infons": {"section_type": "TITLE"},
"text": "Article title..."
},
{
"offset": 42,
"infons": {"section_type": "ABSTRACT"},
"text": "Abstract text..."
},
{
"offset": 500,
"infons": {"section_type": "INTRO"},
"text": "Introduction text..."
}
]
}]
}
```
Section types: `TITLE`, `ABSTRACT`, `INTRO`, `METHODS`, `RESULTS`, `DISCUSS`, `CONCL`, `REF`, `SUPPL`, `FIG`, `TABLE`
**Coverage:** ~3 million articles from the PMC Open Access Subset.
## PMC ID Converter API
Converts between PMID, PMCID, DOI, and Manuscript ID.
### Base URL
```
https://pmc.ncbi.nlm.nih.gov/tools/idconv/api/v1/articles/
```
### Parameters
| Parameter | Required | Description |
|-----------|----------|-------------|
| `ids` | Yes | Up to 200 comma-separated IDs |
| `idtype` | No | `pmcid`, `pmid`, `mid`, `doi` (default: auto-detect) |
| `format` | No | `json`, `xml`, `csv` (default: xml) |
| `tool` | Recommended | Your application name |
| `email` | Recommended | Your contact email |
**Example:**
```
https://pmc.ncbi.nlm.nih.gov/tools/idconv/api/v1/articles/?ids=PMC7029759&format=json
```
**Response:**
```json
{
"status": "ok",
"records": [{
"pmcid": "PMC7029759",
"pmid": "32117569",
"doi": "10.12688/f1000research.22211.2"
}]
}
```
Only returns results for articles that are in PMC. If an article is in PubMed but not PMC, no PMCID will be returned.
## Rate Limits
| Service | Limit |
|---------|-------|
| E-utilities (`db=pmc`) | 3/sec without key, 10/sec with key |
| BioC API | Follow general NCBI policy (3/sec without key) |
| ID Converter | Follow general NCBI policy |
Include `tool` and `email` parameters on E-utility requests. Large batch jobs should run outside peak hours (Mon-Fri 5AM-9PM ET).