A regular expression that matches nothing looks exactly like one that matches everything. This tool shows the matches, takes the pattern apart piece by piece and points out the parts that behave differently from what they look like.
Regex Tester & Explainer
OTHER TOOLS
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- BigQuery GA4 Query & UNNEST Builder
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- Code Beautifier – JavaScript, PHP, Python, SQL & More
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- Consent Mode v2 Decoder
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- DataLayer Inspector & Validator
- DateConverter – Unix Epoch Timestamp & ISO
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- GA4 Bot Detector
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- GTM Duplicates Analyser
- GTM Naming Convention Auditer
- IP Anonymization & Masking Tester
- JSON Beautifier
- JSON-LD Structured Data Generator & Checker
- JWT & OAuth Token Inspector
- LLM / Ollama VRAM & Memory Requirement Estimator
- LLM API Token & Cost Calculator
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- Meta & TikTok CAPI Dedup & Hash Generator
- Modbus & SunSpec Register Decoder
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- RAG Chunking & Embedding Planner
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- Regex Tester & Explainer
- robots.txt & llms.txt Generator for AI Crawlers
- RTSP Stream URL Builder & Vendor Reference
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- Text & Code Diff
- Traefik Label & Compose Generator
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- URL Pretty Print
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