Deploy at the site root as /robots.txt (UTF-8, plain text). Test with Search Console’s robots tester and your server logs.
About this tool
The SynthQuery Robots.txt Generator is a privacy-first, browser-based editor for the plain-text file that tells compliant crawlers which URLs they may fetch on your site. Instead of memorizing RFC 9309 line order or copying decade-old snippets from forums, you compose multiple User-agent groups, mix Allow and Disallow path prefixes, attach Crawl-delay hints where they still matter, enumerate every XML sitemap you want discovered, optionally emit a Host line for Yandex-style canonicalization, and layer helpful comments your engineering team can read six months later. One-click presets cover allow-all defaults, full staging lockdown, WordPress-shaped admin rules, a cautious Next.js API guardrail pattern, and a separate matrix that blocks several widely documented AI training and browsing bots while keeping a permissive wildcard group for traditional search engines—always subject to each vendor’s current documentation and your legal counsel’s interpretation. You can paste an existing robots.txt to reverse-engineer it into structured fields, append individual bot names from a curated quick-insert list, export UTF-8 robots.txt for your CDN or origin, and keep working drafts in local storage between visits. The utility ships inside our Free tools program next to the HTML Online Viewer, Word Counter, Dictionary, Grammar Checker, and related calculators, while the full product catalog on /tools adds AI detection, readability scoring, plagiarism review, and rewriting when your crawl policy conversation turns into on-page copy quality work.
What this tool does
Robots.txt is not a firewall: it is a voluntary protocol. Well-behaved crawlers read the file at the domain root before aggressive fetching, interpret the most specific User-agent stanza that matches their token, then apply Allow and Disallow rules as path-prefix matchers with longest-match precedence in modern Google-style implementations. Because the semantics are easy to misunderstand, SynthQuery surfaces structure instead of a single textarea alone. Each User-agent block lists the token exactly as bots identify themselves (for example Googlebot, Bingbot, or * for “all unmatched agents”), followed by an ordered list of Allow and Disallow rows you can add or remove without hand-counting blank lines.
The generator serializes RFC-style output continuously: comments you type in the preamble become # lines, optional header comments cite the Robot Exclusion Protocol and remind you to validate with Search Console, and duplicate-group warnings appear when two blocks reuse the same token—because merged evaluation is legal but confusing. Crawl-delay is included for teams that still coordinate with crawlers that honor it, with an explicit in-app warning that Google ignores Crawl-delay for Googlebot so you do not mistake the field for a throttle that solves indexing spikes by itself. Multiple Sitemap directives are supported because large news and e-commerce estates often shard feeds; Host is isolated behind labeling that it is not a Google signal.
Advanced workflows lean on import: paste production robots.txt, click apply, and the parser reconstructs groups, retains leading comment banners, and preserves sitemap and host directives when recognizable. Presets speed bootstrapping—allow-all uses an empty Disallow under *, disallow-all uses Disallow: / for staging domains, WordPress adds common wp-admin paths plus an admin-ajax exception, Next.js illustrates blocking internal data routes you might not want cached, and the AI-focused preset stacks dedicated user agents such as GPTBot, Google-Extended, and Claude-Web with Disallow: / while leaving a final * group permissive so you can compare policies side by side before editing. Quick-insert buttons append a new group per bot name so you do not mistype tokens when legal approves a phased rollout.
Everything executes locally in your tab: no robots configuration is uploaded for server-side rendering. That design choice matches security reviews for staging credentials, unreleased collection names, or acquisition diligence environments where even metadata feels sensitive. Download hands you a ready-to-commit robots.txt file; Copy places the same string on the clipboard for Terraform, Kubernetes ConfigMaps, or chat ops threads. Together, these affordances aim for “infrastructure-grade clarity” without turning the page into an enterprise SaaS gate—you can still finish in under a minute when all you need is a sitemap line and a polite default.
Use cases
Growth and SEO teams use the generator when launching a new subdomain: clone the parent policy, add environment-specific disallow rules for /checkout experiments, enumerate hreflang sitemap indexes, and attach the file to the release ticket so developers know exactly what shipped. Engineering leads pair it with infrastructure-as-code reviews—generated text diff cleanly in Git, and comments document intent for SREs who inherit the repo. Content compliance groups reference the AI-bot preset as a starting point for conversations with counsel: robots.txt expresses crawl preference, not copyright grants, but aligning technical signals with published terms reduces crossed wires.
E-commerce merchandisers block faceted navigation floods while allowing product detail pages, using Allow exceptions ahead of broader Disallow rows for parameterized paths. Publishers with subscription paywalls sometimes disallow free crawler agents from member-only paths while permitting verified bots—SynthQuery does not judge business models, but the structured editor makes those nuanced stacks easier to iterate than notepad.exe. International sites add Host only when Yandex remains strategically important and SEO managers understand the directive’s limited scope elsewhere.
Agencies maintain a library of starter templates per CMS; they import a client’s legacy file, reconcile duplicate user agents, append fresh sitemap URLs after migrations, and export before DNS cutover. Educators teaching technical SEO can demonstrate longest-match behavior by reordering rows live and re-copying output into classroom slides. Students comparing careers in search engineering learn that robots.txt interacts with meta robots, canonical tags, HTTP authentication, and CDN edge rules—this tool focuses on the text file itself so those other layers stay visible in lecture notes rather than hidden inside a black-box SaaS crawler simulator.
When marketing copy must align with crawl policy—hero pages that mention “ask your rep about AI training opt-out,” for example—teams jump from this utility to the Grammar Checker and SynthRead for tone, or to the AI Detector when disclosure language is sensitive. Long-form articles about robots rules can be checked with the Plagiarism Checker before publication, and the Word Counter helps keep changelog entries concise when policy updates roll out to clients.
How SynthQuery compares
Lightweight robots “generators” on the web often emit a single User-agent: * block, ignore Allow entirely, omit sitemap validation hints, or hard-code bot lists that went stale two product rebrands ago. Enterprise crawler-management suites go the opposite direction—workflow tickets, SSO, and price tags aimed at Fortune 500 crawl budgets. SynthQuery targets practitioners who need faithful syntax, multiple groups, import/export, and honest notes about vendor-specific behavior, bundled beside the rest of our free utilities and the broader /tools suite. The comparison table highlights practical differences without naming third-party products directly.
Single textarea templates or one-block forms with no import parsing.
AI / LLM policy starters
Preset plus per-bot quick inserts with reminders to verify current bot names with each vendor.
Static bot lists that may not track renamed agents or new entrants.
Privacy posture
Runs in the browser; drafts stored locally; download/copy only when you choose.
Some hosted tools log inputs server-side—check their privacy policies.
Workflow adjacency
Same ecosystem as HTML viewer, word stats, dictionary, grammar, and full AI writing tools.
Standalone robots pages disconnected from copy-editing workflows.
Honest limits
Not a substitute for server auth, WAF rules, legal contracts, or per-URL meta directives.
Occasional marketing implying robots.txt alone blocks scraping or guarantees AI opt-out.
How to use this tool effectively
Start from the environment you are editing: production, staging, or a country subdirectory matters because absolute sitemap URLs and path prefixes must match how visitors resolve the host. If a site is new, pick Allow all crawlers preset, add one or more https Sitemap lines that return 200 OK in the browser, and deploy robots.txt at the root before you announce launch—Search Console’s robots report catches typos early.
When migrating CMS platforms, import the legacy robots file first. Merge duplicate User-agent stanzas mentally: if two * blocks exist, crawlers combine them, which can create surprises. Reorder Allow and Disallow rows so the longest meaningful prefix wins under your target engine’s rules; the generator preserves your ordering so you stay explicit. Add Disallow rows for truly private areas—cart, account, internal search parameters—then verify those URLs are also password-protected or noindexed if secrecy matters, because malicious actors ignore robots.txt.
For staging servers, use disallow-all preset, confirm DNS or basic auth still blocks casual visitors, and remove the lockdown before go-live. If you block AI crawlers, document the business rationale in ticket history; update tokens when vendors rename bots. After editing, click Download, commit the file to version control, purge CDN caches if the edge caches text/plain, and retest with in-url robots.txt fetch plus Search Console. When accompanying landing pages need polished prose about your crawl policy, open the Grammar Checker; when articles explain the change to customers, run SynthRead for reading level and the Word Counter for editorial limits.
Limitations and best practices
Robots.txt is voluntary: scrapers, security probes, and poorly written scripts may ignore it. It does not remove URLs from Google’s index by itself—use removal tools, authentication, or noindex where appropriate. Google generally ignores Crawl-delay for Googlebot; fixing crawl budget usually requires site speed, internal linking hygiene, canonical consistency, and Search Console settings. Host applies mainly in Yandex’s historical interpretation; Google does not use Host in robots.txt for canonical selection. AI-related User-agent tokens change; confirm each provider’s documentation and consult counsel before relying on robots for compliance outcomes alone.
Syntax mistakes—UTF-8 BOM quirks, accidental whitespace in paths, or mixing unrelated directives into wrong groups—can silently broaden or narrow coverage. Always test after deployment, keep a changelog entry when marketing or legal requests edits, and pair robots rules with sitemap hygiene (only 200 URLs, accurate lastmod when truthful). When you need to preview HTML that accompanies crawl messaging, use the HTML Online Viewer; when optimizing images referenced in cleaned URLs, consider the WebP Converter. Finally, bookmark /free-tools for the full free utility hub and /tools for every SynthQuery capability when your project graduates from crawl text to full content intelligence workflows.
Switch between design units when documenting responsive breakpoints mentioned alongside crawl-friendly URL patterns.
Frequently asked questions
Robots.txt is a plain-text file served at the root of a site—https://example.com/robots.txt—that compliant automated agents are encouraged to read before crawling. It follows the Robots Exclusion Protocol (RFC 9309) and contains records: typically User-agent lines naming a crawler token, followed by Allow or Disallow path prefixes, optional Crawl-delay in some ecosystems, Sitemap URLs, and occasionally Host for limited engines. It is not HTML, not JSON, and not a plugin; your web server or CDN must return it with a 200 status and a sensible content-type (usually text/plain). If the file is missing, crawlers generally assume no extra restrictions beyond their own policies. SynthQuery helps you author that file with correct line breaks and comments, but deployment remains your responsibility.
No. Robots.txt is a polite request directed at cooperating bots. Malicious scrapers, vulnerability scanners, and misconfigured tools may ignore it entirely. Sensitive areas should use authentication, network segmentation, rate limiting, WAF rules, and appropriate noindex or noarchive signals where suitable. Think of robots.txt as traffic management for well-behaved crawlers, not as access control. Security teams still require defense in depth; marketing teams should avoid publishing secret URLs in robots.txt because curious humans can read the same file. When in doubt, keep private apps off the public internet or behind SSO rather than relying on Disallow alone.
For Googlebot-class crawlers, matching uses the longest prefix rule among applicable Allow and Disallow lines in the relevant User-agent group (plus inherited defaults when you use multiple groups). An Allow for a specific subdirectory can override a broader Disallow when the Allow is more specific—exact precedence rules depend on the engine, so test in Search Console. Empty Disallow means “no disallow rules from this line,” while Disallow: / blocks the entire site for that user agent. Order in SynthQuery reflects the order in the exported file; you can reorder rows to match your mental model. Always verify with official documentation when stakes are high, because Bing, Google, Yandex, and niche bots may differ subtly.
Crawl-delay requests a pause between requests for agents that honor it. However, Google has stated it does not use Crawl-delay for Googlebot; attempting to slow Google via robots.txt is ineffective for that bot. Some other crawlers historically respected crawl-delay, but support varies and spammy bots ignore it. If you need Google to crawl slower or faster, use Search Console crawl rate settings where available, fix server performance, reduce low-value URL proliferation, and improve canonical signals. SynthQuery still lets you record Crawl-delay when your policy targets a specific bot that documents support—just read the warning we surface when your group looks like Googlebot.
Add one Sitemap: line per absolute URL, each on its own row, typically at the end of the file for human readability though placement is not semantically special. Include only URLs that return valid sitemap XML (often gzip-compressed sitemap files are also acceptable if your stack serves them correctly). Large sites may list a sitemap index that points to child sitemaps. After deployment, open each URL in a browser or curl from a server to confirm 200 responses. SynthQuery’s multi-row sitemap editor keeps lists ordered; blank rows are omitted from export. Pair sitemap hygiene with internal linking and Search Console submission for faster discovery, especially for new pages.
Not directly. Robots.txt controls crawling, not indexing in all cases—Google may still index a URL without crawling it if signals exist elsewhere, showing a snippet-less result. To remove or suppress content, combine techniques: noindex on pages you can fetch, 404/410 for gone resources, authentication for private content, and Search Console removal requests for urgent cases. Updating robots.txt alone without addressing duplicates, canonicals, or backlinks may leave indexed URLs lingering. Treat robots as one layer in a stack that includes metadata, HTTP status, and site architecture. SynthQuery’s educational copy here is informational, not legal advice.
Some vendors publish specific User-agent tokens (for example variants of GPTBot, Claude-Web, or Google-Extended) and guidance about robots.txt. Policies change frequently; verify the latest documentation and your contracts. SynthQuery provides a preset and quick-insert buttons as a starting point: they append Disallow: / groups per token while leaving a separate * group permissive in the AI preset so traditional search bots are not blocked by default. That preset is not legal advice and may not match your jurisdiction, industry, or publisher agreements. You should still coordinate with counsel, measure server logs to see which agents actually visit, and understand that determined actors may not honor robots directives. For broader content strategy, explore SynthQuery’s AI Detector and related tools when drafting disclosure language.
Host: example.com was historically interpreted by Yandex as a hint for the preferred host of a mirror. Google does not support Host in robots.txt for selecting canonical hosts. If your SEO strategy targets Yandex specifically, consult current Yandex webmaster docs before relying on Host; otherwise you can leave the field blank. Misapplied Host lines confuse teammates more than they help on Google-centric stacks. SynthQuery labels the field clearly so you do not assume cross-engine behavior. Prefer HTTPS redirects, consistent internal links, and proper canonical link elements for hostname consolidation on Google.
No. Generation happens in your browser. You copy or download the text and deploy via Git, FTP, S3, Kubernetes, or your hosting UI. Local storage may remember your draft between visits on the same device; clear site data if you share a machine. This architecture keeps staging details off our servers and aligns with how security teams expect low-level infra snippets to be handled. If you need collaborative editing, paste the export into your team’s existing review system—Pull Requests are ideal because line-based diffs highlight policy changes.
Fetch https://yourdomain/robots.txt in a private window, confirm 200 OK, UTF-8 readability, and no unintended caching of an old version at the CDN. Use Google Search Console’s robots testing tool where available to preview URL blocks for Googlebot. Monitor server logs for unexpected 403s on sitemap URLs referenced in the file. Re-run tests whenever you launch new path prefixes, faceted navigation schemes, or international path patterns. If you maintain separate hosts for regions, each may need its own robots.txt. SynthQuery accelerates drafting; production validation remains an operational task.
Staging environments often use Disallow: / for all agents to reduce duplicate content risk and accidental indexing, sometimes combined with password protection. Production files usually open crawling for public marketing pages while restricting admin, cart, and internal APIs. Remember to replace staging rules before DNS cutover—launch incidents sometimes trace to forgotten disallow-all lines. Version-control robots.txt alongside application config so rollbacks are easy. SynthQuery’s staging preset is a blunt instrument: pair it with auth and environment banners so human testers do not confuse environments.
Visit /free-tools for the curated Free tools hub—HTML Online Viewer, Word Counter, Dictionary, Grammar Checker, image converters, calculators, and this generator—then open /tools for the complete AI suite: detection, humanization, plagiarism, SynthRead readability, summarization, translation, and more. Internal links on this page highlight common next steps: polish documentation with the Grammar Checker, tune article length with the Word Counter, or analyze drafts with the AI Detector when policies reference machine-generated content. Bookmark both hubs so engineers and marketers share the same starting points.