SemRush Research

Pull live SEO and competitive intelligence data from the SemRush API.

Prerequisites

Requires SEMRUSH_API_KEY set in .env, .env.local, or ~/.claude/.env.global.

# Verify the key is available
echo "SEMRUSH_API_KEY is ${SEMRUSH_API_KEY:+set}"

If the key is not set, instruct the user:

You need a SemRush API key. Get one at https://www.semrush.com/api/ Then add SEMRUSH_API_KEY=your_key to your .env file.

API Base

All requests go to https://api.semrush.com/ with the API key passed as &key={SEMRUSH_API_KEY}.

Responses are semicolon-delimited CSV. The first line is the header row. Parse accordingly.

---

1. Domain Overview

Get a high-level snapshot of any domain's organic and paid search performance.

Endpoint

https://api.semrush.com/?type=domain_ranks&key={KEY}&export_columns=Dn,Rk,Or,Ot,Oc,Ad,At,Ac&domain={domain}

Export Columns

Column	Meaning
Dn	Domain
Rk	SemRush Rank
Or	Organic keywords count
Ot	Organic traffic estimate
Oc	Organic traffic cost ($)
Ad	Paid keywords count
At	Paid traffic estimate
Ac	Paid traffic cost ($)

Example curl

curl -s "https://api.semrush.com/?type=domain_ranks&key=${SEMRUSH_API_KEY}&export_columns=Dn,Rk,Or,Ot,Oc,Ad,At,Ac&domain=example.com"

Parsing the Response

# Response format (semicolon-delimited):
# Dn;Rk;Or;Ot;Oc;Ad;At;Ac
# example.com;12345;8234;145000;234500;120;3400;5600

# Parse with awk
curl -s "..." | awk -F';' 'NR==2 {
  printf "Domain: %s\nSemRush Rank: %s\nOrganic Keywords: %s\nOrganic Traffic: %s\nOrganic Traffic Cost: $%s\nPaid Keywords: %s\nPaid Traffic: %s\nPaid Traffic Cost: $%s\n",
  $1,$2,$3,$4,$5,$6,$7,$8
}'

---

2. Keyword Overview

Get search volume, CPC, competition, and SERP features for a keyword.

Endpoint

https://api.semrush.com/?type=phrase_all&key={KEY}&phrase={keyword}&database=us&export_columns=Ph,Nq,Cp,Co,Nr,Td

Export Columns

Column	Meaning
Ph	Keyword phrase
Nq	Search volume (monthly)
Cp	CPC (USD)
Co	Competition (0-1)
Nr	Number of results
Td	Trend (12 months, comma-separated)

Example curl

curl -s "https://api.semrush.com/?type=phrase_all&key=${SEMRUSH_API_KEY}&phrase=content+marketing&database=us&export_columns=Ph,Nq,Cp,Co,Nr,Td"

Supported Databases

Use &database=XX where XX is: us, uk, ca, au, de, fr, es, it, br, in, jp.

---

3. Related Keywords

Find semantically related keywords for content planning and gap analysis.

Endpoint

https://api.semrush.com/?type=phrase_related&key={KEY}&phrase={keyword}&database=us&export_columns=Ph,Nq,Cp,Co,Nr,Td&display_limit=20

Example curl

curl -s "https://api.semrush.com/?type=phrase_related&key=${SEMRUSH_API_KEY}&phrase=project+management&database=us&export_columns=Ph,Nq,Cp,Co,Nr,Td&display_limit=20"

Parsing Multiple Rows

curl -s "..." | awk -F';' 'NR>1 { printf "%-40s Vol: %-8s CPC: $%-6s Comp: %s\n", $1, $2, $3, $4 }'

---

4. Keyword Difficulty

Estimate how hard it is to rank for a keyword.

Endpoint

https://api.semrush.com/?type=phrase_kdi&key={KEY}&phrase={keyword}&database=us&export_columns=Ph,Kd

Column	Meaning
Ph	Keyword
Kd	Keyword difficulty (0-100)

Interpretation:

• 0-29: Easy - achievable with quality content
• 30-49: Moderate - needs solid content + some backlinks
• 50-69: Hard - needs strong domain authority + backlinks
• 70-84: Very hard - requires established authority
• 85-100: Extremely hard - dominated by top-tier domains

---

5. Domain Organic Keywords

See which keywords a domain ranks for organically.

Endpoint

https://api.semrush.com/?type=domain_organic&key={KEY}&domain={domain}&database=us&export_columns=Ph,Po,Nq,Cp,Url,Tr,Tc&display_limit=50&display_sort=tr_desc

Column	Meaning
Ph	Keyword
Po	Position
Nq	Search volume
Cp	CPC
Url	Ranking URL
Tr	Traffic (%)
Tc	Traffic cost

Example curl

curl -s "https://api.semrush.com/?type=domain_organic&key=${SEMRUSH_API_KEY}&domain=hubspot.com&database=us&export_columns=Ph,Po,Nq,Cp,Url,Tr,Tc&display_limit=20&display_sort=tr_desc"

---

6. Backlink Overview

Get a summary of a domain's backlink profile.

Endpoint

https://api.semrush.com/analytics/v1/?key={KEY}&type=backlinks_overview&target={domain}&target_type=root_domain&export_columns=total,domains_num,urls_num,ips_num,follows_num,nofollows_num,texts_num,images_num

Example curl

curl -s "https://api.semrush.com/analytics/v1/?key=${SEMRUSH_API_KEY}&type=backlinks_overview&target=example.com&target_type=root_domain&export_columns=total,domains_num,urls_num,ips_num,follows_num,nofollows_num,texts_num,images_num"

---

7. Competitor Discovery

Find domains competing for the same organic keywords.

Endpoint

https://api.semrush.com/?type=domain_organic_organic&key={KEY}&domain={domain}&database=us&export_columns=Dn,Cr,Np,Or,Ot,Oc,Ad&display_limit=10

Column	Meaning
Dn	Competitor domain
Cr	Competition level
Np	Common keywords
Or	Organic keywords
Ot	Organic traffic
Oc	Organic traffic cost
Ad	Paid keywords

Example curl

curl -s "https://api.semrush.com/?type=domain_organic_organic&key=${SEMRUSH_API_KEY}&domain=notion.so&database=us&export_columns=Dn,Cr,Np,Or,Ot,Oc,Ad&display_limit=10"

---

8. Traffic Analytics (Estimates)

Estimate a domain's overall traffic sources and engagement.

Endpoint

https://api.semrush.com/analytics/ta/api/v3/summary?key={KEY}&targets={domain}&display_date=2024-01-01&country=us&export_columns=target,visits,users,bounce_rate,pages_per_visit,avg_visit_duration

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Workflow: Full Competitive Analysis

When the user asks for a full competitive analysis, run these steps in order:

1. Domain Overview - Get the target domain's metrics
2. Competitor Discovery - Find top 5-10 competitors
3. Domain Overview for each competitor - Compare metrics
4. Top Keywords for each domain - Find keyword gaps
5. Backlink Overview for each domain - Compare link profiles

Output Format

Present results as a comparison table:

| Metric              | target.com | competitor1.com | competitor2.com |
|---------------------|-----------|-----------------|-----------------|
| SemRush Rank        | ...       | ...             | ...             |
| Organic Keywords    | ...       | ...             | ...             |
| Organic Traffic     | ...       | ...             | ...             |
| Traffic Cost        | ...       | ...             | ...             |
| Backlinks           | ...       | ...             | ...             |
| Referring Domains   | ...       | ...             | ...             |

Then highlight:

• Keyword gaps: Keywords competitors rank for but target does not
• Quick wins: Keywords where target ranks positions 5-20 (improvement opportunities)
• Content gaps: Topics competitors cover but target does not
• Backlink opportunities: Sites linking to competitors but not target

Rate Limits and Costs

• Each API call costs API units (check your plan)
• Use &display_limit= to control result count (default varies by endpoint)
• Cache results locally when doing multi-step analysis to avoid redundant calls
• Domain overview calls are cheapest; backlink and traffic analytics cost more

Error Handling

Error	Meaning
ERROR 50 :: NOTHING FOUND	No data for this query
ERROR 120 :: WRONG KEY	Invalid API key
ERROR 130 :: LIMIT EXCEEDED	API unit limit reached
Empty response	Usually means no data available for the query parameters

When you get "NOTHING FOUND", try:

• Different database (e.g., uk instead of us)
• Root domain instead of subdomain
• Broader keyword phrase