traceOn

Turns raw browser performance traces into a plain-language diagnosis of what's slow, why, and what to fix first.

traceOn turns a raw browser performance trace into a plain-language diagnosis of what's slow on a web page, why, and what to fix first. Most performance tools hand you a flame chart and leave the interpretation to you. traceOn does the interpretation. You click Record, it captures a DevTools-Protocol trace of the tab you choose, analyzes it entirely on your own machine, and gives you a readable report. 𝗣𝗿𝗶𝘃𝗮𝗰𝘆: 𝗔𝗹𝗹 𝗮𝗻𝗮𝗹𝘆𝘀𝗶𝘀 𝗵𝗮𝗽𝗽𝗲𝗻𝘀 𝗹𝗼𝗰𝗮𝗹𝗹𝘆. 𝘁𝗿𝗮𝗰𝗲𝗢𝗻 𝘄𝗼𝗿𝗸𝘀 𝗳𝘂𝗹𝗹𝘆 𝘄𝗶𝘁𝗵 𝗻𝗼 𝗮𝗰𝗰𝗼𝘂𝗻𝘁 𝗮𝗻𝗱 𝗻𝗼 𝗻𝗲𝘁𝘄𝗼𝗿𝗸 𝗰𝗼𝗻𝗻𝗲𝗰𝘁𝗶𝗼𝗻. 𝗘𝘃𝗲𝗿𝘆 𝗳𝗲𝗮𝘁𝘂𝗿𝗲 𝘁𝗵𝗮𝘁 𝘀𝗲𝗻𝗱𝘀 𝗮𝗻𝘆𝘁𝗵𝗶𝗻𝗴 𝗼𝗳𝗳 𝘆𝗼𝘂𝗿 𝗱𝗲𝘃𝗶𝗰𝗲 𝗶𝘀 𝗼𝗳𝗳 𝗯𝘆 𝗱𝗲𝗳𝗮𝘂𝗹𝘁 𝗮𝗻𝗱 𝗰𝗹𝗲𝗮𝗿𝗹𝘆 𝗹𝗮𝗯𝗲𝗹𝗲𝗱. 𝗡𝗼 𝗮𝗱𝘀, 𝗻𝗼 𝘁𝗵𝗶𝗿𝗱-𝗽𝗮𝗿𝘁𝘆 𝘁𝗿𝗮𝗰𝗸𝗲𝗿𝘀, 𝗻𝗼 𝗱𝗮𝘁𝗮 𝘀𝗮𝗹𝗲𝘀. 𝗙𝘂𝗹𝗹 𝗽𝗼𝗹𝗶𝗰𝘆: 𝗵𝘁𝘁𝗽𝘀://𝘁𝗿𝗮𝗰𝗲𝗼𝗻-𝗰𝗼𝗺𝗺𝘂𝗻𝗶𝘁𝘆.𝘀𝗼𝗹𝗼𝗺𝗼𝗻-𝗺𝘂𝗵𝘆𝗲-𝘄𝗱.𝘄𝗼𝗿𝗸𝗲𝗿𝘀.𝗱𝗲𝘃/𝗽𝗿𝗶𝘃𝗮𝗰𝘆 What you get from one recording: • A performance score with the specific reasons behind it — not just a number. • Core Web Vitals — LCP, CLS, INP, FCP, TTFB and Total Blocking Time, each explained in context. • Ranked bottlenecks — the handful of things actually costing you load time, ordered by impact, with the long tasks and scripts responsible. • Diagnoses — concrete problems traceOn detected (render-blocking resources, layout thrash, oversized main-thread work, late LCP element, and more), each with a confidence level. • Recommendations — prioritized fixes with their expected impact, tailored to the framework it detects on your page. • A "Load Story" timeline — a narrative walkthrough of how the page came together, millisecond by millisecond, instead of a wall of trace spans. More tools built in: • Security checks — response-header analysis (CSP, HSTS, X-Frame-Options and others) plus cookie metadata review (Secure/HttpOnly/SameSite flags, oversized cookies) for the page under analysis. • Responsive preview — view your page at multiple device sizes side by side. • DevTools panel — a convenience panel for a quick Web Vitals read without a full recording. • AI assistant (optional) — ask questions about your own analysis; it works from a compressed summary, never your raw trace. • Community tab (optional) — anonymized, domain-level score aggregates, top-site lists, and a Q&A board. 𝗣𝗿𝗶𝘃𝗮𝗰𝘆: 𝗔𝗹𝗹 𝗮𝗻𝗮𝗹𝘆𝘀𝗶𝘀 𝗵𝗮𝗽𝗽𝗲𝗻𝘀 𝗹𝗼𝗰𝗮𝗹𝗹𝘆. 𝘁𝗿𝗮𝗰𝗲𝗢𝗻 𝘄𝗼𝗿𝗸𝘀 𝗳𝘂𝗹𝗹𝘆 𝘄𝗶𝘁𝗵 𝗻𝗼 𝗮𝗰𝗰𝗼𝘂𝗻𝘁 𝗮𝗻𝗱 𝗻𝗼 𝗻𝗲𝘁𝘄𝗼𝗿𝗸 𝗰𝗼𝗻𝗻𝗲𝗰𝘁𝗶𝗼𝗻. 𝗘𝘃𝗲𝗿𝘆 𝗳𝗲𝗮𝘁𝘂𝗿𝗲 𝘁𝗵𝗮𝘁 𝘀𝗲𝗻𝗱𝘀 𝗮𝗻𝘆𝘁𝗵𝗶𝗻𝗴 𝗼𝗳𝗳 𝘆𝗼𝘂𝗿 𝗱𝗲𝘃𝗶𝗰𝗲 𝗶𝘀 𝗼𝗳𝗳 𝗯𝘆 𝗱𝗲𝗳𝗮𝘂𝗹𝘁 𝗮𝗻𝗱 𝗰𝗹𝗲𝗮𝗿𝗹𝘆 𝗹𝗮𝗯𝗲𝗹𝗲𝗱. 𝗡𝗼 𝗮𝗱𝘀, 𝗻𝗼 𝘁𝗵𝗶𝗿𝗱-𝗽𝗮𝗿𝘁𝘆 𝘁𝗿𝗮𝗰𝗸𝗲𝗿𝘀, 𝗻𝗼 𝗱𝗮𝘁𝗮 𝘀𝗮𝗹𝗲𝘀. 𝗙𝘂𝗹𝗹 𝗽𝗼𝗹𝗶𝗰𝘆: 𝗵𝘁𝘁𝗽𝘀://𝘁𝗿𝗮𝗰𝗲𝗼𝗻-𝗰𝗼𝗺𝗺𝘂𝗻𝗶𝘁𝘆.𝘀𝗼𝗹𝗼𝗺𝗼𝗻-𝗺𝘂𝗵𝘆𝗲-𝘄𝗱.𝘄𝗼𝗿𝗸𝗲𝗿𝘀.𝗱𝗲𝘃/𝗽𝗿𝗶𝘃𝗮𝗰𝘆 Made for: web developers, performance engineers, and anyone who needs to know why a page feels slow.