Below we provide a list of JavaScript API keywords frequently used by fingerprinting scripts. To this end, we measure the relative prevalence of API keywords in fingerprinting scripts by computing the ratio of their fraction of occurrence in fingerprinting scripts to their fraction of occurrence in non-fingerprinting scripts. A higher value of the ratio for a keyword means that it is more prevalent in fingerprinting scripts than non-fingerprinting scripts. Note that infinity means that the keyword is only present in fingerprinting scripts. For example, a value of 1.0 means that we only observe that keyword in fingerprinting scripts, whereas a value of 0.5 means we observe it in an equal number of fingerprinting and non-fingerprinting scripts.
Table includes keywords that have pervasiveness values greater than or equal to 10. Scripts (count) represents the number of distinct fingerprinting scripts in which the keyword is used and Websites (count) represents the number of websites on which those scripts are embedded.
| API Keywords | Ratio | Scripts (count) | Websites (count) |
|---|---|---|---|
| onpointerleave | infinity |
4 | 1366 |
| StereoPannerNode | infinity |
1 | 1363 |
| FontFaceSetLoadEvent | infinity |
1 | 1363 |
| PresentationConnectionAvailableEvent | infinity |
1 | 1363 |
| MediaDeviceInfo | infinity |
1 | 1363 |
| msGetRegionContent | infinity |
1 | 1363 |
| peerIdentity | infinity |
1 | 1363 |
| MSManipulationEvent | infinity |
1 | 1363 |
| VideoStreamTrack | infinity |
1 | 1363 |
| mozSetImageElement | infinity |
1 | 1363 |
| magnetometer | infinity |
215 | 241 |
| requestWakeLock | infinity |
1 | 174 |
| PresentationRequest | infinity |
16 | 16 |
| audioWorklet | infinity |
3 | 8 |
| onwebkitanimationiteration | infinity |
3 | 3 |
| onpointerenter | infinity |
3 | 3 |
| onwebkitanimationstart | infinity |
3 | 3 |
| onlostpointercapture | infinity |
3 | 3 |
| RTCCertificate | infinity |
2 | 2 |
| PresentationConnectionList | infinity |
1 | 1 |
| onMSVideoOptimalLayoutChanged | infinity |
1 | 1 |
| PresentationAvailability | infinity |
1 | 1 |
| BaseAudioContext | infinity |
1 | 1 |
| activeVRDisplays | infinity |
1 | 1 |
| BluetoothRemoteGATTCharacteristic | infinity |
1 | 1 |
| VisualViewport | infinity |
1 | 1 |
| PresentationConnection | infinity |
1 | 1 |
| onMSVideoFormatChanged | infinity |
1 | 1 |
| onMSVideoFrameStepCompleted | infinity |
1 | 1 |
| BluetoothDevice | infinity |
1 | 1 |
| onuserproximity | 543.77 | 18 | 18 |
| ongotpointercapture | 362.52 | 3 | 3 |
| onpointerout | 362.52 | 3 | 3 |
| accelerometer | 326.71 | 219 | 247 |
| chargingchange | 302.10 | 20 | 20 |
| onafterscriptexecute | 217.51 | 18 | 1380 |
| channelCountMode | 199.03 | 28 | 39 |
| getDevices | 187.62 | 59 | 80 |
| maxChannelCount | 184.44 | 29 | 40 |
| baseLatency | 181.26 | 3 | 8 |
| onpointerover | 181.26 | 3 | 3 |
| onbeforescriptexecute | 181.26 | 18 | 1380 |
| onicegatheringstatechange | 179.78 | 61 | 61 |
| MediaDevices | 161.12 | 4 | 1366 |
| numberOfInputs | 157.09 | 26 | 36 |
| channelInterpretation | 147.69 | 11 | 22 |
| speedOfSound | 140.98 | 7 | 11 |
| dopplerFactor | 140.98 | 7 | 11 |
| midi | 138.72 | 225 | 251 |
| ondeviceproximity | 131.35 | 25 | 282 |
| HTMLMenuItemElement | 121.40 | 218 | 244 |
| updateCommands | 120.84 | 1 | 1363 |
| FRAGMENT_SHADER_DERIVATIVE_HINT_OES | 120.84 | 1 | 2 |
| getSupportedProfiles | 120.84 | 1 | 2 |
| initCompositionEvent | 120.84 | 1 | 1 |
| initAnimationEvent | 120.84 | 1 | 1 |
| vrdisplayfocus | 120.84 | 1 | 1 |
| initTransitionEvent | 120.84 | 1 | 1 |
| vrdisplayblur | 120.84 | 1 | 1 |
| exportKey | 105.97 | 57 | 57 |
| onauxclick | 90.63 | 3 | 3 |
| microphone | 90.43 | 223 | 250 |
| iceGatheringState | 90.30 | 68 | 1481 |
| ondevicelight | 88.31 | 19 | 36 |
| renderedBuffer | 87.17 | 189 | 439 |
| WebGLContextEvent | 82.52 | 28 | 44 |
| ondeviceorientationabsolute | 80.56 | 4 | 1366 |
| startRendering | 79.33 | 193 | 458 |
| createOscillator | 78.77 | 191 | 445 |
| knee | 76.65 | 170 | 419 |
| OfflineAudioContext | 74.68 | 199 | 721 |
| timeLog | 72.50 | 12 | 12 |
| getFloatFrequencyData | 72.50 | 6 | 10 |
| WEBGL_compressed_texture_atc | 72.50 | 3 | 4 |
| illuminance | 72.50 | 3 | 3 |
| reduction | 69.64 | 170 | 419 |
| modulusLength | 69.39 | 58 | 58 |
| WebGL2RenderingContext | 68.71 | 29 | 30 |
| enumerateDevices | 64.12 | 208 | 666 |
| AmbientLightSensor | 63.60 | 10 | 267 |
| attack | 61.31 | 173 | 434 |
| AudioWorklet | 60.42 | 22 | 32 |
| Worklet | 60.42 | 22 | 32 |
| AudioWorkletNode | 60.42 | 22 | 32 |
| lastStyleSheetSet | 60.42 | 1 | 1363 |
| DeviceProximityEvent | 60.42 | 1 | 1363 |
| DeviceLightEvent | 60.42 | 1 | 1363 |
| enableStyleSheetsForSet | 60.42 | 1 | 1363 |
| UserProximityEvent | 60.42 | 1 | 1363 |
| vrdisplaydisconnect | 60.42 | 1 | 1 |
| mediaDevices | 60.03 | 230 | 850 |
| vibrate | 57.68 | 232 | 1793 |
| vendorSub | 56.17 | 251 | 1728 |
| setValueAtTime | 55.29 | 167 | 417 |
| getChannelData | 55.18 | 195 | 460 |
| MAX_DRAW_BUFFERS_WEBGL | 54.93 | 10 | 12 |
| reliable | 52.36 | 39 | 103 |
| WEBGL_draw_buffers | 52.09 | 25 | 27 |
| EXT_sRGB | 51.79 | 3 | 4 |
| setSinkId | 50.35 | 5 | 1367 |
| namedCurve | 50.29 | 67 | 74 |
| minDecibels | 48.34 | 2 | 2 |
| UNKNOWN_ERR | 48.34 | 2 | 2 |
| WEBGL_debug_shaders | 45.31 | 3 | 4 |
| productSub | 42.79 | 734 | 2819 |
| hardwareConcurrency | 41.92 | 716 | 3661 |
| publicExponent | 41.52 | 67 | 74 |
| requestMIDIAccess | 40.28 | 1 | 1363 |
| mozIsLocallyAvailable | 40.28 | 1 | 174 |
| ondevicemotion | 40.28 | 4 | 4 |
| maxDecibels | 40.28 | 2 | 2 |
| getLayoutMap | 40.28 | 1 | 1 |
| Animatable | 40.28 | 1 | 1 |
| GeckoActiveXObject | 40.28 | 1 | 1 |
| XPathResult | 39.73 | 218 | 417 |
| mozBattery | 39.04 | 42 | 322 |
| IndexedDB | 38.73 | 25 | 25 |
| generateKey | 37.46 | 62 | 62 |
| buildID | 36.52 | 272 | 414 |
| getSupportedExtensions | 36.46 | 534 | 1007 |
| MAX_TEXTURE_MAX_ANISOTROPY_EXT | 35.85 | 521 | 980 |
| oscpu | 35.33 | 681 | 1196 |
| oninvalid | 34.75 | 65 | 1428 |
| vpn | 34.53 | 24 | 24 |
| lastEventID | 34.53 | 2 | 2 |
| mozCaptureStream | 34.53 | 2 | 2 |
| createDynamicsCompressor | 33.54 | 189 | 442 |
| privateKey | 33.46 | 67 | 74 |
| EXT_texture_filter_anisotropic | 32.91 | 479 | 949 |
| isPointInPath | 32.17 | 481 | 949 |
| getContextAttributes | 31.76 | 460 | 920 |
| BatteryManager | 31.23 | 23 | 50 |
| getShaderPrecisionFormat | 30.81 | 450 | 915 |
| depthFunc | 30.81 | 452 | 921 |
| uniform2f | 30.71 | 460 | 930 |
| rangeMax | 30.36 | 449 | 902 |
| rangeMin | 30.24 | 446 | 897 |
| EXT_disjoint_timer_query | 30.21 | 3 | 4 |
| scrollByPages | 30.21 | 1 | 1363 |
| CanvasCaptureMediaStreamTrack | 30.21 | 1 | 18 |
| onlanguagechange | 30.21 | 4 | 4 |
| RTCDataChannelEvent | 30.21 | 1 | 2 |
| onMSFullscreenChange | 30.21 | 1 | 1 |
| clearColor | 29.16 | 457 | 916 |
| createWriter | 28.93 | 17 | 17 |
| getUniformLocation | 28.61 | 466 | 948 |
| getAttribLocation | 28.58 | 464 | 945 |
| drawArrays | 28.53 | 466 | 948 |
| useProgram | 28.37 | 467 | 949 |
| enableVertexAttribArray | 28.37 | 466 | 948 |
| createShader | 28.31 | 467 | 949 |
| compileShader | 28.30 | 467 | 936 |
| shaderSource | 28.27 | 466 | 936 |
| attachShader | 28.25 | 464 | 934 |
| bufferData | 28.24 | 466 | 938 |
| linkProgram | 28.23 | 464 | 933 |
| vertexAttribPointer | 28.22 | 464 | 933 |
| bindBuffer | 28.14 | 463 | 932 |
| createProgram | 27.95 | 464 | 934 |
| OES_standard_derivatives | 27.46 | 20 | 1384 |
| appCodeName | 27.03 | 325 | 1890 |
| getAttributeNodeNS | 26.49 | 16 | 21 |
| ARRAY_BUFFER | 25.36 | 471 | 941 |
| suffixes | 25.14 | 775 | 1441 |
| TouchEvent | 25.01 | 481 | 1130 |
| MIDIPort | 24.17 | 2 | 19 |
| MAX_COLOR_ATTACHMENTS_WEBGL | 24.17 | 1 | 2 |
| lowpass | 24.17 | 1 | 1 |
| onaudioprocess | 23.64 | 9 | 17 |
| showModalDialog | 23.56 | 39 | 1419 |
| globalStorage | 23.48 | 245 | 1681 |
| camera | 22.76 | 229 | 255 |
| onanimationiteration | 22.66 | 3 | 3 |
| webkitNotification | 21.97 | 2 | 2 |
| textBaseline | 21.76 | 888 | 3234 |
| MediaStreamTrackEvent | 21.32 | 3 | 1365 |
| deviceproximity | 21.13 | 25 | 26 |
| taintEnabled | 20.89 | 14 | 24 |
| alphabetic | 20.65 | 671 | 2986 |
| userproximity | 20.28 | 24 | 25 |
| globalCompositeOperation | 20.15 | 507 | 975 |
| outputBuffer | 20.14 | 12 | 34 |
| WebGLUniformLocation | 20.14 | 1 | 1363 |
| WebGLShaderPrecisionFormat | 20.14 | 1 | 1363 |
| OffscreenCanvas | 20.14 | 1 | 1 |
| MIDIInput | 20.14 | 1 | 1 |
| ServiceWorkerContainer | 20.14 | 1 | 1 |
| pranswer | 20.14 | 1 | 1 |
| ScriptProcessorNode | 20.14 | 1 | 1 |
| MIDIAccess | 20.14 | 1 | 1 |
| vrdisplayconnect | 20.14 | 1 | 1 |
| customelements | 20.14 | 1 | 1 |
| SVGAnimationElement | 20.14 | 1 | 1 |
| createScriptProcessor | 20.14 | 11 | 20 |
| createBuffer | 19.98 | 472 | 954 |
| UIEvent | 19.93 | 47 | 63 |
| toSource | 19.54 | 416 | 2224 |
| createAnalyser | 19.33 | 12 | 17 |
| fillRect | 19.22 | 898 | 3432 |
| requestAutocomplete | 18.59 | 2 | 2 |
| evenodd | 18.49 | 504 | 960 |
| fillText | 18.09 | 957 | 3502 |
| candidate | 18.03 | 178 | 1847 |
| WEBGL_debug_renderer_info | 17.83 | 406 | 2214 |
| toDataURL | 17.64 | 951 | 3507 |
| dischargingTime | 17.53 | 38 | 54 |
| bluetooth | 17.28 | 225 | 424 |
| vrdisplaydeactivate | 17.26 | 1 | 1 |
| MediaKeySession | 17.26 | 1 | 1 |
| vrdisplayactivate | 17.26 | 1 | 1 |
| FLOAT | 16.89 | 467 | 939 |
| battery | 16.82 | 152 | 1853 |
| devicelight | 16.51 | 25 | 26 |
| onanimationstart | 16.48 | 3 | 3 |
| getExtension | 16.43 | 575 | 1115 |
| onemptied | 16.11 | 4 | 4 |
| captureStream | 16.11 | 2 | 2 |
| MediaStreamTrack | 15.90 | 10 | 10 |
| WebGLRenderingContext | 15.75 | 472 | 2432 |
| oncomplete | 15.70 | 256 | 505 |
| onratechange | 15.59 | 4 | 4 |
| fillStyle | 15.55 | 962 | 3517 |
| getGamepads | 15.10 | 14 | 1807 |
| BiquadFilterNode | 15.10 | 1 | 1363 |
| SVGZoomEvent | 15.10 | 1 | 1363 |
| filterNumber | 15.10 | 1 | 1 |
| NotSupported | 15.10 | 1 | 1 |
| PermissionStatus | 15.10 | 1 | 1 |
| ignoreBOM | 15.10 | 1 | 1 |
| queryInfo | 15.10 | 1 | 1 |
| onspeechend | 15.10 | 1 | 1 |
| maxTouchPoints | 15.09 | 741 | 2700 |
| frequencyBinCount | 14.87 | 8 | 12 |
| credential | 14.82 | 66 | 66 |
| iceTransportPolicy | 14.65 | 4 | 4 |
| iceCandidatePoolSize | 14.50 | 3 | 3 |
| DeviceMotionEvent | 14.26 | 40 | 1603 |
| rtcpMuxPolicy | 14.22 | 4 | 4 |
| webgl | 14.17 | 557 | 1510 |
| indexedDB | 13.92 | 887 | 3095 |
| rotationAngle | 13.85 | 22 | 22 |
| setTargetAtTime | 13.73 | 5 | 5 |
| iceServers | 13.62 | 195 | 519 |
| clipboard | 13.59 | 233 | 260 |
| onconnectionstatechange | 13.43 | 2 | 2 |
| connectionstatechange | 13.43 | 2 | 2 |
| meetOrSlice | 13.43 | 1 | 1 |
| remoteCandidateId | 13.43 | 1 | 1 |
| channelCount | 13.17 | 34 | 45 |
| getParameter | 13.08 | 581 | 1112 |
| selectionDirection | 13.01 | 7 | 7 |
| closePath | 12.98 | 513 | 970 |
| NetworkInformation | 12.95 | 9 | 266 |
| emma | 12.95 | 3 | 3 |
| createOffer | 12.68 | 176 | 480 |
| languages | 12.57 | 699 | 2950 |
| setLocalDescription | 12.46 | 178 | 495 |
| requestFileSystem | 12.39 | 28 | 1080 |
| createDataChannel | 12.33 | 173 | 477 |
| onicecandidate | 12.32 | 175 | 1841 |
| Float32Array | 12.30 | 534 | 1024 |
| requestPointerLock | 12.08 | 2 | 1365 |
| ValidityState | 12.08 | 1 | 1363 |
| onwebkitresourcetimingbufferfull | 12.08 | 1 | 1363 |
| gathering | 12.08 | 4 | 4 |
| MediaQueryList | 12.08 | 1 | 1 |
| tooltipNode | 12.08 | 1 | 1 |
| drawWindow | 12.08 | 1 | 1 |
| Sensor | 12.08 | 1 | 1 |
| TEMPORARY | 12.05 | 129 | 227 |
| SpeechRecognition | 11.79 | 4 | 4 |
| recognition | 11.69 | 3 | 3 |
| beginPath | 11.59 | 523 | 1079 |
| smoothingTimeConstant | 11.51 | 2 | 2 |
| systemLanguage | 11.50 | 672 | 1375 |
| acceleration | 11.46 | 48 | 236 |
| multiply | 11.36 | 527 | 986 |
| arc | 11.35 | 528 | 1193 |
| fonts | 11.35 | 474 | 2553 |
| gbk | 11.33 | 21 | 21 |
| outerText | 11.31 | 22 | 23 |
| deriveBits | 11.19 | 10 | 17 |
| doNotTrack | 11.16 | 871 | 2847 |
| publicKey | 11.07 | 75 | 82 |
| storageArea | 10.99 | 6 | 6 |
| EMS | 10.99 | 2 | 2 |
| xMaxYMin | 10.99 | 1 | 1 |
| DataError | 10.99 | 1 | 1 |
| remoteId | 10.99 | 1 | 1 |
| RTCPeerConnection | 10.97 | 171 | 1963 |
| createMediaStreamSource | 10.74 | 4 | 4 |
| getImageData | 10.56 | 255 | 293 |
| bundlePolicy | 10.36 | 3 | 3 |
| PERSISTENT | 10.28 | 4 | 21 |
| ANGLE_instanced_arrays | 10.07 | 4 | 1367 |
| hasPointerCapture | 10.07 | 2 | 1364 |
| focusMode | 10.07 | 2 | 3 |
| xMidYMin | 10.07 | 1 | 1 |