🔊 分贝仪（在线噪音检测）Decibel Meter (Noise Level Test)
用手机或电脑麦克风实时测量环境噪音分贝，显示当前、最小、平均（Leq）和最大分贝，附 60 秒曲线图和常见噪音对照表，支持 A 计权和手动校准，检测装修、邻居、马路噪音是否超标。Measure ambient noise in decibels with your phone or computer microphone: live, minimum, average (Leq) and maximum dB, a 60-second chart and a reference table, with A-weighting and manual calibration — check whether neighbours, renovation or traffic noise is too loud.
校准（让读数更准确）Calibration (for better accuracy)
手机和电脑麦克风灵敏度不同，读数是估算值。有专业分贝仪或已知声源（例如安静卧室约 30 dB）时，调整偏移让两者一致即可，设置会保存在本机。Microphones differ, so readings are estimates. If you have a reference meter or a known source (a quiet bedroom is about 30 dB), adjust the offset to match; it is saved on this device.
常见噪音分贝参考Typical noise levels
使用说明与常见问题How-to & FAQ
「分贝仪（在线噪音检测）」是什么？What is the Decibel Meter (Noise Level Test)?
用手机或电脑麦克风实时测量环境噪音分贝，显示当前、最小、平均（Leq）和最大分贝，附 60 秒曲线图和常见噪音对照表，支持 A 计权和手动校准，检测装修、邻居、马路噪音是否超标。Measure ambient noise in decibels with your phone or computer microphone: live, minimum, average (Leq) and maximum dB, a 60-second chart and a reference table, with A-weighting and manual calibration — check whether neighbours, renovation or traffic noise is too loud.
如何使用「分贝仪（在线噪音检测）」？How do I use the Decibel Meter (Noise Level Test)?
点“开始测量噪音”，允许浏览器使用麦克风，把手机放在要测量的位置，读数会实时更新。测量一段时间后看“平均（Leq）”，它最能代表这段时间的噪音水平。需要更准确时，在“校准”里调整偏移。Press Start, allow microphone access and place the device where you want to measure; the reading updates live. After a while, read the Average (Leq) — it best represents the noise over that period. Adjust the offset under Calibration for better accuracy.
手机测的分贝准吗？How accurate is a phone decibel meter?
手机麦克风没有经过专业校准，并且会对很大的声音自动限幅，所以读数是估算值，误差一般在 ±5 dB 左右。用来判断“安静 / 吵闹 / 很吵”足够；需要作为投诉或执法证据时，请使用经过检定的专业声级计。Phone microphones are not calibrated and clip very loud sounds, so readings are estimates, typically within about ±5 dB. That is enough to tell quiet from loud; for complaints or legal evidence use a certified sound level meter.
多少分贝算噪音扰民？How many decibels counts as a noise nuisance?
按国家《声环境质量标准》，居住区（1 类区）白天不超过 55 dB、夜间（22:00–6:00）不超过 45 dB；室内夜间一般建议低于 30–35 dB 才不影响睡眠。长期处在 85 dB 以上会损伤听力。For residential areas, typical limits are 55 dB by day and 45 dB at night (22:00–06:00); indoors at night below 30–35 dB is recommended for sleep. Long exposure above 85 dB damages hearing.
A 计权是什么意思？What does A-weighting mean?
人耳对低频和极高频的声音不敏感，A 计权会按人耳的灵敏度给不同频率加权，测得的值记作 dB(A)，是噪音标准里最常用的单位。关闭 A 计权则对所有频率一视同仁。The ear is less sensitive to low and very high frequencies; A-weighting applies the ear’s sensitivity curve, giving dB(A), the unit used in most noise standards. Turning it off weighs all frequencies equally.
「分贝仪（在线噪音检测）」免费吗？文件会上传吗？Is the Decibel Meter (Noise Level Test) free? Are my files uploaded?
「分贝仪（在线噪音检测）」完全免费，无需注册。麦克风声音只在本机实时分析，不录音、不保存、不上传，点“停止”或关闭页面后立即释放麦克风。The Decibel Meter (Noise Level Test) is free with no sign-up. Microphone sound is analysed live on your device only — never recorded, stored or uploaded — and the microphone is released when you press Stop or close the page.