# Backlink Checker API - Referring Domains & Competitor Gap (`doesaiknow/backlink-checker-api-referring-domains-competitor-gap`) Actor Backlink checker API - referring domains, anchors & competitor backlink gap for any domain. Native data, pay-per-result, no subscription. An Ahrefs/Semrush alternative. - **URL**: https://apify.com/doesaiknow/backlink-checker-api-referring-domains-competitor-gap.md - **Developed by:** [Dawid S](https://apify.com/doesaiknow) (community) - **Categories:** SEO tools, E-commerce, Automation - **Stats:** 1 total users, 0 monthly users, 100.0% runs succeeded, 0 bookmarks - **User rating**: No ratings yet ## Pricing from $105.00 / 1,000 domain backlink summaries This Actor is paid per event and usage. You are charged both the fixed price for specific events and for Apify platform usage. Since this Actor supports Apify Store discounts, the price gets lower the higher subscription plan you have. Learn more: https://docs.apify.com/platform/actors/running/actors-in-store#pay-per-event ## What's an Apify Actor? Actors are a software tools running on the Apify platform, for all kinds of web data extraction and automation use cases. 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. Actors are written with capital "A". ## 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. The best way to integrate Actors is as follows. In JavaScript/TypeScript projects, use official [JavaScript/TypeScript client](https://docs.apify.com/api/client/js.md): ```bash npm install apify-client ``` In Python projects, use official [Python client library](https://docs.apify.com/api/client/python.md): ```bash pip install apify-client ``` In shell scripts, use [Apify CLI](https://docs.apify.com/cli/docs.md): ````bash # MacOS / Linux curl -fsSL https://apify.com/install-cli.sh | bash # Windows irm https://apify.com/install-cli.ps1 | iex ```bash In AI frameworks, you might use the [Apify MCP server](https://docs.apify.com/platform/integrations/mcp.md). If your project is in a different language, use the [REST API](https://docs.apify.com/api/v2.md). For usage examples, see the [API](#api) section below. For more details, see Apify documentation as [Markdown index](https://docs.apify.com/llms.txt) and [Markdown full-text](https://docs.apify.com/llms-full.txt). # README ## Backlink Checker API — Referring Domains, Competitor Gap & Backlink Profile · Ahrefs / Semrush Alternative **Enter a domain, get its full backlink profile via API — total backlinks, referring domains, spam score, and the *competitor backlink gap*: the domains that link to your rivals but not to you.** Pay per result, no $99–$199/month subscription, no contract. Native backlink-index data via API — not a fragile UI scraper. > **Coverage on par with Ahrefs — measured, not claimed.** In side-by-side tests our referring-domain coverage matched or beat Ahrefs: an established site returned **1,737 referring domains vs Ahrefs' 1,600**; a brand-new site **43 vs 32**. You get a credible backlink index at a fraction of a tool subscription. *(We don't reproduce Ahrefs' proprietary DR score — see [FAQ](#-faq).)* Built for **link builders, SEO & PR agencies, sales / lead-gen teams**, and **developers** wiring backlink data into pipelines via API or MCP. --- ### ⚡ Quick start — 30 seconds Click **`Try for free`**. The default input runs a real backlink summary on a live domain — actual JSON in seconds. Then swap in your own: ```json { "domains": ["monday.com"], "mode": "summary" } ```` **Sample output** (real run, trimmed): ```json { "mode": "summary", "target": "monday.com", "rank": 644, "backlinks": 8975219, "referring_domains": 72896, "referring_main_domains": 63603, "referring_domains_nofollow": 9683, "broken_backlinks": 138276, "backlinks_spam_score": 19, "first_seen": "2019-01-15" } ``` *** ### 🎯 Three modes | `mode` | Input | One dataset row per target | |---|---|---| | **`summary`** *(default)* | `domains` | full profile: rank, backlinks, referring domains (total / main / nofollow), broken backlinks, spam score, first seen | | **`referring_domains`** | `domains`, `limit` | ranked list — each `{ domain, rank, backlinks, spam score, first seen }` | | **`competitor_gap`** ⭐ | `domains`, `competitors`, `limit` | domains that link to your competitors **but not to you** — your ready-made link-building target list | **`competitor_gap` is the one no free tool gives you.** Drop in 2–3 rivals and get the exact referring domains you're missing — the highest-intent link-prospecting list there is. *** ### 🚀 Input | field | type | default | notes | |---|---|---|---| | `domains` | string\[] | — *(required)* | target domains; auto-normalized (scheme/path/`www.` stripped, IDN→punycode, lowercased) and deduped | | `mode` | enum | `summary` | `summary` | `referring_domains` | `competitor_gap` | | `competitors` | string\[] | — | required for `competitor_gap`; rival domains | | `limit` | int (1–1000) | 100 | rows for the list modes (ignored by `summary`) | | `includeSubdomains` | bool | `true` | count subdomains toward the target | ```jsonc // referring domains — top 50 by rank { "domains": ["monday.com"], "mode": "referring_domains", "limit": 50 } // competitor gap — who links to asana & clickup but not monday { "domains": ["monday.com"], "mode": "competitor_gap", "competitors": ["asana.com", "clickup.com"], "limit": 100 } ``` ### 📊 Output One dataset item per target domain: - **summary** → `{ target, rank, backlinks, referring_domains, referring_main_domains, referring_domains_nofollow, broken_backlinks, backlinks_spam_score, first_seen }` - **referring\_domains** → `{ target, count, referring_domains_list: [{ domain, rank, backlinks, backlinks_spam_score, first_seen }] }` - **competitor\_gap** → `{ target, competitors, gap_count, gap: [{ domain, rank, links_to[] }] }` Export as JSON / CSV / Excel, or pull live via the Apify API (`run-sync-get-dataset-items`). ### 💰 Pricing — pay per result, flat per report You pay **per domain, not per row** — same price whether you pull 20 rows or 1,000. | event | price / domain | when | |---|---|---| | `actor-start` | $0.005 | once per run, after input validation | | `domain-summary` | $0.15 | after a successful summary | | `referring-domains-report` | $0.20 | after a successful referring-domains list (any `limit`) | | `competitor-gap-report` | $0.25 | after a successful competitor-gap report (any `limit`) | Charged **only after** data is delivered — failed or empty calls bill nothing beyond `actor-start`. A per-run cost cap (`MAX_RUN_COST_USD`, default $5) stops the run before overspend. **Example:** a competitor gap on your domain vs 2 rivals (top 100 prospects) = `$0.005 + $0.25 = $0.255`. The same workflow in Ahrefs/Semrush needs a $99–$199/month seat. **Free Apify plan:** capped to **1 domain, `summary` mode** per run — you still see your domain's real profile (referring-domain count, broken links, spam score). Popular domains return instantly from a built-in preview cache; any other domain gets one real live summary so you can preview your own site. The ranked referring-domains list and the competitor gap require a paid plan. ### 🆚 How it compares **vs. Ahrefs / Semrush / Moz** — no $99–$199/month subscription; pay per domain checked. API-first JSON straight into your sheet, CRM, n8n/Make/Zapier, or AI agent. Referring-domain coverage on par (measured). Trade-off: we don't reproduce Ahrefs' proprietary **DR** — we return a 0–1000 domain rank + backlink spam score. **vs. other Apify backlink actors** — most scrape the Ahrefs/Semrush UI: fragile (break on UI change), ToS-risky, only as available as the SaaS login. This actor uses a **native data API** — stable, no scraping, no proxy roulette — and adds a value layer (competitor gap, spam signal, clean typed output, free preview). **vs. raw data-API providers** — no monthly minimum commitment, no API-key management, no per-endpoint billing math. Pay per result, scale to zero. ### 🧭 Who it's for - **Link builders / SEO agencies** — `competitor_gap` = instant prospecting list; `referring_domains` = profile audit. - **Content & PR teams** — see who links to the competition, pitch the same outlets. - **Sales / lead-gen** — a rival's referring domains are warm outreach signals. - **Developers & AI agents** — backlink data as a clean JSON API / MCP tool, billed per call. ### 🔌 API & integrations Run from the **Apify API** (incl. `run-sync-get-dataset-items` for a single request/response call), official **JS / Python clients**, CLI, or any HTTP client — see the **API** tab. Pipe results to Google Sheets, Slack, n8n, Make, Zapier via Apify integrations. *(MCP server for AI agents on the roadmap.)* ### 🛡️ Legal & compliance Uses a licensed native backlink data API. Public link-graph data only — no login-walled or personal data. ToS-safe (no identical-request hammering; built-in run cache). ### 🧰 FAQ **Is the coverage as good as Ahrefs?** On referring domains, yes in our tests (1,737 vs 1,600 established; 43 vs 32 new). Backlink indexes never match exactly — we surface a credible, native index at pay-per-result pricing. **Do you return Domain Rating (DR)?** No — DR is Ahrefs' proprietary score. We return a domain rank (0–1000) + backlink spam score for relative authority/quality. **How am I billed?** Per result, after delivery (see Pricing). Free / failed / empty calls don't bill beyond `actor-start`. A per-run cost cap prevents surprises. **Where does the data come from?** A licensed, enterprise-grade backlink-data API — not a UI scraper. Stable, no proxies. **Can it monitor new / lost backlinks?** On the roadmap (v0.2) — scheduled new/lost diffs + alerts. v1 is on-demand lookups. ### 🗺️ Roadmap **v0.2:** new/lost backlink monitoring (scheduled diffs + Slack/email alerts), anchor-text breakdown, bulk mode (≤1000 domains/call), disavow-list export. **+ MCP server** for AI agents. ### 🏷️ Keywords backlink checker api, backlink api, referring domains, ahrefs alternative, semrush alternative, competitor backlinks, backlink gap, link building tool, backlink analysis, backlink profile, referring domains checker, backlink spam checker, free ahrefs alternative, broken backlink checker, link gap analysis, who links to my website ### 🤝 Built by [**doesaiknow**](https://apify.com/doesaiknow) — semantic-SEO & LLM-search APIs on Apify Store. Pay-per-result, no subscription, MCP-ready. More tools: - [**Keyword Search Volume API**](https://apify.com/doesaiknow/doesaiknow-keyword-metrics-apify) — Google + Bing search volume, CPC & 12-month trends, bulk. - [**AI Keyword Clustering Tool**](https://apify.com/doesaiknow/ai-keyword-clustering-tool-topical-clustering-bulk-serp) — cluster up to 1,000 keywords into a SERP-validated topical map. - [**AI Brand Visibility Tracker**](https://apify.com/doesaiknow/ai-brand-visibility-tracker-chatgpt-perplexity-gemini) — see where your brand shows up in ChatGPT, Perplexity & Gemini answers. # Actor input Schema ## `domains` (type: `array`): One or more target domains to analyze (e.g. monday.com). Each is normalized (scheme/path/`www.` stripped, lowercased) and deduplicated before any upstream API call (identical tasks are not refundable per upstream API ToS). One dataset row is produced per unique domain. FREE PLAN: limited to 1 domain and `summary` mode only — the actor exits early with an upgrade prompt above the limit. Paid plans: multiple domains, all modes. ## `mode` (type: `string`): What to return per domain. 'summary' = backlink profile (rank, backlinks, referring domains, spam, broken) — the default. 'referring\_domains' = ranked list of referring domains. 'competitor\_gap' = domains linking to your competitors but NOT to your target (requires the Competitors field). FREE PLAN is forced to 'summary'. ## `competitors` (type: `array`): Rival domains for `competitor_gap` mode. The actor returns referring domains that link to these competitors but NOT to your target — your backlink prospecting list. Ignored in other modes. Normalized + deduplicated like `domains`. ## `limit` (type: `integer`): Maximum rows returned for `referring_domains` and `competitor_gap` modes. Ignored by `summary`. Higher limits cost more (per-row billing). 1–1000. ## `includeSubdomains` (type: `boolean`): Treat the target as a whole domain including its subdomains (e.g. blog.monday.com counts toward monday.com). Passed through to the upstream API. Default true. ## Actor input object example ```json { "domains": [ "monday.com" ], "mode": "summary", "competitors": [ "asana.com", "clickup.com" ], "limit": 100, "includeSubdomains": true } ``` # Actor output Schema ## `backlinks` (type: `string`): Default dataset link. One row per unique target domain, shaped by mode. See dataset\_schema.json for per-field documentation. # 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 '' with your token const client = new ApifyClient({ token: '', }); // Prepare Actor input const input = { "domains": [ "monday.com" ], "competitors": [ "asana.com", "clickup.com" ] }; // Run the Actor and wait for it to finish const run = await client.actor("doesaiknow/backlink-checker-api-referring-domains-competitor-gap").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 '' with your token. client = ApifyClient("") # Prepare the Actor input run_input = { "domains": ["monday.com"], "competitors": [ "asana.com", "clickup.com", ], } # Run the Actor and wait for it to finish run = client.actor("doesaiknow/backlink-checker-api-referring-domains-competitor-gap").call(run_input=run_input) # Fetch and print Actor results from the run's dataset (if there are any) print("💾 Check your data here: https://console.apify.com/storage/datasets/" + run["defaultDatasetId"]) for item in client.dataset(run["defaultDatasetId"]).iterate_items(): print(item) # 📚 Want to learn more 📖? Go to → https://docs.apify.com/api/client/python/docs/quick-start ``` ## CLI example ```bash echo '{ "domains": [ "monday.com" ], "competitors": [ "asana.com", "clickup.com" ] }' | apify call doesaiknow/backlink-checker-api-referring-domains-competitor-gap --silent --output-dataset ``` ## MCP server setup ```json { "mcpServers": { "apify": { "command": "npx", "args": [ "mcp-remote", "https://mcp.apify.com/?tools=doesaiknow/backlink-checker-api-referring-domains-competitor-gap", "--header", "Authorization: Bearer " ] } } } ``` ## OpenAPI specification ```json { "openapi": "3.0.1", "info": { "title": "Backlink Checker API - Referring Domains & Competitor Gap", "description": "Backlink checker API - referring domains, anchors & competitor backlink gap for any domain. Native data, pay-per-result, no subscription. An Ahrefs/Semrush alternative.", "version": "0.0", "x-build-id": "oaTggqrDPusTl8pQn" }, "servers": [ { "url": "https://api.apify.com/v2" } ], "paths": { "/acts/doesaiknow~backlink-checker-api-referring-domains-competitor-gap/run-sync-get-dataset-items": { "post": { "operationId": "run-sync-get-dataset-items-doesaiknow-backlink-checker-api-referring-domains-competitor-gap", "x-openai-isConsequential": false, "summary": "Executes an Actor, waits for its completion, and returns Actor's dataset items in response.", "tags": [ "Run Actor" ], "requestBody": { "required": true, "content": { "application/json": { "schema": { "$ref": "#/components/schemas/inputSchema" } } } }, "parameters": [ { "name": "token", "in": "query", "required": true, "schema": { "type": "string" }, "description": "Enter your Apify token here" } ], "responses": { "200": { "description": "OK" } } } }, "/acts/doesaiknow~backlink-checker-api-referring-domains-competitor-gap/runs": { "post": { "operationId": "runs-sync-doesaiknow-backlink-checker-api-referring-domains-competitor-gap", "x-openai-isConsequential": false, "summary": "Executes an Actor and returns information about the initiated run in response.", "tags": [ "Run Actor" ], "requestBody": { "required": true, "content": { "application/json": { "schema": { "$ref": "#/components/schemas/inputSchema" } } } }, "parameters": [ { "name": "token", "in": "query", "required": true, "schema": { "type": "string" }, "description": "Enter your Apify token here" } ], "responses": { "200": { "description": "OK", "content": { "application/json": { "schema": { "$ref": "#/components/schemas/runsResponseSchema" } } } } } } }, "/acts/doesaiknow~backlink-checker-api-referring-domains-competitor-gap/run-sync": { "post": { "operationId": "run-sync-doesaiknow-backlink-checker-api-referring-domains-competitor-gap", "x-openai-isConsequential": false, "summary": "Executes an Actor, waits for completion, and returns the OUTPUT from Key-value store in response.", "tags": [ "Run Actor" ], "requestBody": { "required": true, "content": { "application/json": { "schema": { "$ref": "#/components/schemas/inputSchema" } } } }, "parameters": [ { "name": "token", "in": "query", "required": true, "schema": { "type": "string" }, "description": "Enter your Apify token here" } ], "responses": { "200": { "description": "OK" } } } } }, "components": { "schemas": { "inputSchema": { "type": "object", "required": [ "domains" ], "properties": { "domains": { "title": "Target domains", "minItems": 1, "maxItems": 100, "type": "array", "description": "One or more target domains to analyze (e.g. monday.com). Each is normalized (scheme/path/`www.` stripped, lowercased) and deduplicated before any upstream API call (identical tasks are not refundable per upstream API ToS). One dataset row is produced per unique domain. FREE PLAN: limited to 1 domain and `summary` mode only — the actor exits early with an upgrade prompt above the limit. Paid plans: multiple domains, all modes.", "items": { "type": "string", "minLength": 1, "maxLength": 253 } }, "mode": { "title": "Mode", "enum": [ "summary", "referring_domains", "competitor_gap" ], "type": "string", "description": "What to return per domain. 'summary' = backlink profile (rank, backlinks, referring domains, spam, broken) — the default. 'referring_domains' = ranked list of referring domains. 'competitor_gap' = domains linking to your competitors but NOT to your target (requires the Competitors field). FREE PLAN is forced to 'summary'.", "default": "summary" }, "competitors": { "title": "Competitors (gap mode only)", "minItems": 0, "maxItems": 10, "type": "array", "description": "Rival domains for `competitor_gap` mode. The actor returns referring domains that link to these competitors but NOT to your target — your backlink prospecting list. Ignored in other modes. Normalized + deduplicated like `domains`.", "items": { "type": "string", "minLength": 1, "maxLength": 253 } }, "limit": { "title": "Row limit (list modes)", "minimum": 1, "maximum": 1000, "type": "integer", "description": "Maximum rows returned for `referring_domains` and `competitor_gap` modes. Ignored by `summary`. Higher limits cost more (per-row billing). 1–1000.", "default": 100 }, "includeSubdomains": { "title": "Include subdomains", "type": "boolean", "description": "Treat the target as a whole domain including its subdomains (e.g. blog.monday.com counts toward monday.com). Passed through to the upstream API. Default true.", "default": true } } }, "runsResponseSchema": { "type": "object", "properties": { "data": { "type": "object", "properties": { "id": { "type": "string" }, "actId": { "type": "string" }, "userId": { "type": "string" }, "startedAt": { "type": "string", "format": "date-time", "example": "2025-01-08T00:00:00.000Z" }, "finishedAt": { "type": "string", "format": "date-time", "example": "2025-01-08T00:00:00.000Z" }, "status": { "type": "string", "example": "READY" }, "meta": { "type": "object", "properties": { "origin": { "type": "string", "example": "API" }, "userAgent": { "type": "string" } } }, "stats": { "type": "object", "properties": { "inputBodyLen": { "type": "integer", "example": 2000 }, "rebootCount": { "type": "integer", "example": 0 }, "restartCount": { "type": "integer", "example": 0 }, "resurrectCount": { "type": "integer", "example": 0 }, "computeUnits": { "type": "integer", "example": 0 } } }, "options": { "type": "object", "properties": { "build": { "type": "string", "example": "latest" }, "timeoutSecs": { "type": "integer", "example": 300 }, "memoryMbytes": { "type": "integer", "example": 1024 }, "diskMbytes": { "type": "integer", "example": 2048 } } }, "buildId": { "type": "string" }, "defaultKeyValueStoreId": { "type": "string" }, "defaultDatasetId": { "type": "string" }, "defaultRequestQueueId": { "type": "string" }, "buildNumber": { "type": "string", "example": "1.0.0" }, "containerUrl": { "type": "string" }, "usage": { "type": "object", "properties": { "ACTOR_COMPUTE_UNITS": { "type": "integer", "example": 0 }, "DATASET_READS": { "type": "integer", "example": 0 }, "DATASET_WRITES": { "type": "integer", "example": 0 }, "KEY_VALUE_STORE_READS": { "type": "integer", "example": 0 }, "KEY_VALUE_STORE_WRITES": { "type": "integer", "example": 1 }, "KEY_VALUE_STORE_LISTS": { "type": "integer", "example": 0 }, "REQUEST_QUEUE_READS": { "type": "integer", "example": 0 }, "REQUEST_QUEUE_WRITES": { "type": "integer", "example": 0 }, "DATA_TRANSFER_INTERNAL_GBYTES": { "type": "integer", "example": 0 }, "DATA_TRANSFER_EXTERNAL_GBYTES": { "type": "integer", "example": 0 }, "PROXY_RESIDENTIAL_TRANSFER_GBYTES": { "type": "integer", "example": 0 }, "PROXY_SERPS": { "type": "integer", "example": 0 } } }, "usageTotalUsd": { "type": "number", "example": 0.00005 }, "usageUsd": { "type": "object", "properties": { "ACTOR_COMPUTE_UNITS": { "type": "integer", "example": 0 }, "DATASET_READS": { "type": "integer", "example": 0 }, "DATASET_WRITES": { "type": "integer", "example": 0 }, "KEY_VALUE_STORE_READS": { "type": "integer", "example": 0 }, "KEY_VALUE_STORE_WRITES": { "type": "number", "example": 0.00005 }, "KEY_VALUE_STORE_LISTS": { "type": "integer", "example": 0 }, "REQUEST_QUEUE_READS": { "type": "integer", "example": 0 }, "REQUEST_QUEUE_WRITES": { "type": "integer", "example": 0 }, "DATA_TRANSFER_INTERNAL_GBYTES": { "type": "integer", "example": 0 }, "DATA_TRANSFER_EXTERNAL_GBYTES": { "type": "integer", "example": 0 }, "PROXY_RESIDENTIAL_TRANSFER_GBYTES": { "type": "integer", "example": 0 }, "PROXY_SERPS": { "type": "integer", "example": 0 } } } } } } } } } } ```