REFRESH RATE TESTER

Detect your monitor's true Hz. Measure frame time, jitter, dropped frames & display performance. Works for 60Hz, 120Hz, 144Hz, 165Hz, 240Hz, 360Hz and beyond.

⚡
REFRESH RATE DETECTOR
Real-time monitor Hz detection via requestAnimationFrame API
LIVE RAF API 60s TEST
--
DETECTED HZ
waiting...
--
FRAME TIME
ms per frame
--
JITTER
ms deviation
0
DROPPED
frames skipped
--
MIN HZ
session low
--
MAX HZ
session high
--
STABILITY
consistency %
0
TOTAL FRAMES
measured
--
PRESS START TO TEST
IDLE — Ready to test
0 frames
⏱ TEST DURATION
🎨 VISUAL PATTERN
🔵BOUNCE
↔️SWEEP
⚡FLICKER
▦GRID
🌀SPIRAL
🌧RAIN
♟CHECKER
💡STROBE
🧪 TEST MODE
⚡ STANDARD Basic Hz detection
🔒 VSYNC CHECK Detect VSync state
🔥 STRESS TEST Hz under CPU load
📐 FRAME PACING 1%/0.1% lows
🎯 PRECISION High-accuracy mode
⏳ LONG RUN 5-min stability
📐 EXTENDED METRICS
--
99th %ile FT
--
1% LOW HZ
--
0.1% LOW HZ
--
AVG FRAME MS
--
STD DEV ms
--
VARIANCE
--
MODE HZ
--
TEAR RISK
📊 FRAME TIME GRAPH LIVE ▸
📊
FRAME TIME GRAPH
Frame delivery consistency over time
LIVE
TARGET: 16.67ms SCALE: 0–33ms
🔬 JITTER ANALYSIS
Frame time variance--
Dropped frame ratio--
Consistency score--
🏆 PERFORMANCE GRADE SCORE ▸
🏆
PERFORMANCE GRADE
Overall display & system performance rating
SCORE
?
Run a test to get your grade
📋 BREAKDOWN
Detected Refresh Rate --
Average Frame Time --
Stability Rating --
Dropped Frames --
🛸UFO MOTION CLARITY TEST VISUAL▸
🛸
UFO MOTION CLARITY TEST
Multiple objects moving at reference Hz speeds — the lane matching your Hz looks sharpest
VISUALCLASSIC
🛸 REFERENCE SPEED LANES
🛸
UFO MOTION CLARITY TEST
Press ▶ START to begin the test
60Hz144Hz240Hz360Hz
The lane that looks sharpest = your Hz
💡 All objects move at the same real speed. Your display can only render whole frames, so the lane matching your Hz will show zero ghosting — all others will blur. The lane that looks crystal clear is your refresh rate.
📐FRAME PACING ANALYZER 1% LOWS▸
📐
FRAME PACING ANALYZER
Percentile distribution, 1% & 0.1% lows, frame time histogram and pacing score
PERCENTILESADVANCED
📊 FRAME TIME HISTOGRAM
--
AVG FT ms
--
50th %ile
--
95th %ile
--
99th %ile
--
1% LOW Hz
--
0.1% LOW Hz
--
PACING SCORE
--
VERDICT
Run the main test first, then analyze
💡 1% Low = Hz your display hits 99% of the time. 0.1% Low = worst-case spikes. A big gap between average and 1% low means microstutter.
🔒VSYNC & TEARING DETECTOR SYNC▸
🔒
VSYNC & TEARING DETECTOR
Detect VSync state, frame pacing consistency, and screen tearing probability
SYNC TESTUNKNOWN
🔒 VSYNC STATUS
--
Run the main test first
Frame consistency
--
Timing regularity
--
Tear probability
--
Adaptive sync est.
--
Estimated VSync latency --
Frame interval deviation --
👁 TEARING VISUAL TEST
A horizontal tear line visible in the moving bar = tearing is occurring. No visible line = VSync or G-Sync/FreeSync active.
🖱️INPUT LAG ESTIMATOR CLICK TEST▸
🖱️
INPUT LAG ESTIMATOR
Measure click-to-visual response — approximates end-to-end display latency at your current Hz
CLICK TESTLATENCY
🖱️ REACTION TARGET
🎯
Click START to begin
0 / 10 rounds
--
AVG ms
--
BEST ms
--
WORST ms
0
MISSES
📊 LAG BREAKDOWN
Frame budget at detected Hz --
Theoretical min display lag --
Estimated render overhead --
Lag grade --
💡 At 60Hz min display lag is ~16.7ms. At 240Hz it's ~4.2ms. Total lag includes OS, mouse firmware, and panel response time.
👻PIXEL RESPONSE & GHOSTING PANEL TEST▸
👻
PIXEL RESPONSE & GHOSTING
Visualize pixel transition speed, motion ghosting severity and panel characteristics
PIXEL RESPPANEL
👁 GHOSTING STRIP
--
px/ms SPEED
--
GHOST LVL
--
CLARITY %
--
PANEL EST.
📋 PANEL RESPONSE REFERENCE
PANEL TYPETYPICAL GtGGHOSTINGBEST FOR
TN1–5msMinimalCompetitive gaming
IPS4–8msLowGeneral / color work
VA8–16msModerateMovies / contrast
OLED<1msNonePremium gaming
⚖️MULTI-HZ COMPARATOR COMPARE▸
⚖️
MULTI-HZ COMPARATOR
Side-by-side simulated motion comparison — see the visual difference between refresh rates
COMPAREVISUAL
⚖️ SIMULATED HZ LANES
💡 Each lane is throttled to its labeled Hz by skipping frames. Higher Hz lanes show less inter-frame distance and appear smoother even on a lower-Hz display.
⚠️MICROSTUTTER DETECTOR STUTTER▸
⚠️
MICROSTUTTER DETECTOR
Detect irregular frame delivery, consecutive frame time spikes and stutter classification
STUTTERADVANCED
⚡ FRAME DELTA TIMELINE
Smooth (<2ms var)
Minor stutter (2–5ms)
Major stutter (>5ms)
0
STUTTERS
--
PER SEC
--
SEVERITY
--
MAX DELTA
--
VERDICT
💡 Microstutter occurs when consecutive frames arrive unevenly — e.g. 8ms then 24ms then 8ms — even if your average Hz is correct. This causes visible judder. A score under 1 stutter/sec = excellent.
📡VRR / ADAPTIVE SYNC RANGE TEST FREESYNC▸
📡
VRR / ADAPTIVE SYNC RANGE TEST
Sweep Hz from low to max to detect your FreeSync / G-Sync / HDMI VRR operating range
VRRG-SYNC / FREESYNC
📡 LIVE VRR READING
--
CURRENT HZ
MINVRR RANGEMAX
306090120165240360
Detected VRR min --
Detected VRR max --
VRR status --
🔧 SWEEP SETTINGS
Sweep from (Hz)
30Hz
Sweep to (Hz)
240Hz
Sweep speed
💡 FreeSync/G-Sync monitors vary Hz dynamically with frame rate. This sweep simulates varying load to probe your VRR range. A VRR-capable display will follow the sweep smoothly.
📈HZ STABILITY TIMELINE TIMELINE▸
📈
HZ STABILITY TIMELINE
Live Hz plotted over 60 seconds — spot thermal throttle, power events, browser interference
LIVE60s LOG
📈 HZ OVER TIME (60s WINDOW)
← 60s ago NOW →
--
MEAN HZ
--
MIN HZ
--
MAX HZ
--
RANGE Δ
0
DIPS <90%
--
STABILITY
📋 NOTABLE EVENTS
Start the main test — events appear here automatically
🔲BROWSER TAB FOCUS TEST TAB TEST▸
🔲
BROWSER TAB FOCUS TEST
Measure how your browser throttles requestAnimationFrame when the tab loses focus
THROTTLEBROWSER
🔲 CURRENT FOCUS STATE
● FOCUSED
--
Hz in this state
--
FOCUSED Hz
--
BLURRED Hz
Throttle ratio --
Focus switches 0
📋 EVENT LOG
Click START, then switch tabs to test throttling...
💡 Most browsers cap RAF at 1 fps or ~1Hz when a tab is backgrounded. Chrome may allow higher. Some browsers also cap at background timer throttling after 5+ seconds of inactivity.
⏱DISPLAY LATENCY CALCULATOR LATENCY▸
⏱
DISPLAY LATENCY CALCULATOR
End-to-end input-to-pixel latency breakdown based on your detected Hz and hardware inputs
LATENCYCALCULATOR
⚙️ HARDWARE INPUTS
1000Hz
4ms
2ms
0ms
AUTO
📊 LATENCY BREAKDOWN
--
ms TOTAL END-TO-END LATENCY
MOUSE
--
→
FRAME
--
→
RENDER
--
→
VSYNC
--
→
PANEL
--
Frame budget at detected Hz --
Latency improvement vs 60Hz --
Latency grade --
🌊SMOOTHNESS PERCEPTION TEST VISUAL▸
🌊
SMOOTHNESS PERCEPTION TEST
Multi-speed scrolling text, moving shapes and flicker test — perceived smoothness score based on Hz
VISUALPERCEPTUAL
🌊 SCROLLING MOTION TEST
Run test with detected Hz — multiple objects at different speeds
🎯 SMOOTHNESS SCORE
--
Run the test to score
Hz adequacy
--
Frame consistency
--
Jitter impact
--
Drop impact
--
📋 HZ PERCEPTION TABLE
HZPERCEPTIONUSE CASE
30ChoppyVideo/film only
60AcceptableEveryday use
120SmoothGaming & browsing
144Very smoothCompetitive gaming
240Ultra smoothEsports
360+DiminishingPro tournaments
⚙️ SETTINGS & CUSTOMIZATION 11 TABS ▸
⚙️
SETTINGS & CUSTOMIZATION
11 tabs — fine-tune every aspect of the test, visuals, audio, export, and more
11 TABSADVANCED
🔧 DETECTION ALGORITHM
📐 Warmup frames
30 frames
Frames ignored before measuring begins
📊 Average window
60 frames
Rolling window size for Hz calculation
🎯 Drop threshold (%)
30%
Frame time % above average = dropped
⚡ Algorithm
Method used to calculate refresh rate
🕐 Stability timeout (s)
3s
Seconds of stable reading before auto-stop
📏 Jitter tolerance (ms)
5ms
Max jitter before flagging instability
🔁 Sampling mode
How frames are sampled per test run
⏱ Min frame time (ms)
2ms
Ignore frames faster than this threshold
🎨 CANVAS APPEARANCE
🌈 Animation speed
4×
💡 Ball / object size
24px
🎨 Trail length
6
🔲 Background style
✨ Glow intensity
5
🎯 Object shape
🌀 Motion blur frames
0
🖼 Canvas height (px)
200px
🔔 OVERLAY OPTIONS
Show Hz overlay on canvas
Show frame time overlay
Show scan line effect
Show dropped frame flash
Auto-stop when stable
Save history automatically
Show grade after test
Animate stat card numbers
Show progress bar during test
Highlight reference table row
Show jitter bars live
Show toast notifications
📍 Overlay position
📝 Overlay font size
12px
🌈 ACCENT COLOR
Quick swatches
🎨 Canvas object color
🎭 UI COLOR PRESETS
🌡 Background tint
0%
📊 GRAPH CONFIGURATION
📈 Graph style
📏 History points
120
🎨 Graph colors
Show target Hz line
Highlight spike frames
Show graph grid lines
Auto-scale Y axis
📐 Graph height (px)
100px
🔊 AUDIO SETTINGS
🔈 Master volume
50%
🎵 Sound events
Sound on test complete
Sound on milestone Hz
Sound on dropped frame
Tick every 10 frames
🎹 Tone type
SINE
SQUARE
SAW
TRI
🎵 Tone frequency (Hz)
440Hz
⏱ Tone duration (ms)
80ms
⌨️ KEYBOARD SHORTCUTS
Test Controls
Start / Stop test
Reset all
Fullscreen test
Export results
Save grade
Navigation & Display
Toggle theme
Next pattern
Prev pattern
Speed up
Speed down
Click any key to re-bind. Press the new key to assign.
📤 EXPORT FORMAT
📋JSON
📊CSV
📄TXT
📦 Export includes
Detected Hz & frame time
All raw frame times
Jitter & stability stats
Performance grade
⚙️ Export options
Include timestamp
Include settings snapshot
Pretty-print JSON
📝 Custom filename prefix
📂 History Management
Max history entries
20
History is saved to localStorage in your browser
✨ CANVAS EFFECTS
⚡ Particle effects
Enable particles
Particle count
20
💫 Glow & bloom
Object glow halo
Pulse glow on drop
Glow size multiplier
2×
🌊 Wave & ripple
Ripple on bounce
Background wave
Wave amplitude
6
📡 Radar / crosshair
Center crosshair
Frame counter overlay
Corner timing marks
🎞 Flicker & CRT
CRT scanlines overlay
Vignette effect
Scanline opacity
15%
🌈 Rainbow & HSL
Rainbow trail mode
HSL cycle on object
Color cycle speed
3
♿ ACCESSIBILITY OPTIONS
🧠 Motion & animation
Reduce canvas motion
Disable all animations
No strobe / flicker
🔤 Text & contrast
UI font size scale
100%
High contrast mode
Bold all UI text
🎨 Color adjustments
Color blind mode
Underline active elements
Large click targets
🔬 ADVANCED & DEVELOPER
🛠 Debug options
Debug mode (console logs)
Log every frame time
Show RAF timestamp delta
Show performance.now() ms
📡 Live system info
Browser--
Hardware concurrency--
Device pixel ratio--
Screen resolution--
Color depth--
⚙️ RAF & timing
Compensate DPR in calc
Force integer Hz rounding
Outlier rejection filter
Outlier sigma threshold
2σ
🗑 Data & Storage
Storage used: --
📋 HZ REFERENCE TABLE DATABASE ▸
📋
HZ REFERENCE TABLE
Common refresh rates & ideal frame times
REFRESH RATE FRAME TIME IDEAL FOR STATUS
🗂 SESSION HISTORY LOG ▸
🗂
SESSION HISTORY
Past results from this session
# HZ FRAME TIME STABILITY GRADE TIME
No sessions yet — run your first test!
❓ WHAT IS REFRESH RATE? GUIDE ▸
📖
REFRESH RATE GUIDE
Everything you need to know about monitor Hz
GUIDE

⚡ What is Refresh Rate?

Monitor refresh rate (measured in Hz) is how many times per second your display updates the image. A 60Hz monitor redraws 60 times per second. Higher Hz = smoother motion. This free refresh rate test uses the requestAnimationFrame API for ultra-accurate detection.

🎮 Which Hz Do I Need?

  • 60Hz — Office, casual use, video
  • 120Hz — Smooth browsing, console gaming
  • 144Hz — Competitive gaming standard
  • 165–240Hz — Esports, FPS games
  • 360Hz+ — Pro-level esports play

🔬 How This Test Works

We call requestAnimationFrame() in a tight loop and measure the timestamp delta between each callback. Over a rolling window of frames, we calculate your display's true refresh rate — including dropped frames and frame time jitter.

📊 What Is Frame Time?

Frame time is the milliseconds between each frame. At 60Hz: 16.67ms. At 144Hz: 6.94ms. At 240Hz: 4.17ms. Lower frame time with minimal variance means smoother animation and a better gaming experience.

⚠️ What Causes Low Hz?

  • Monitor set to wrong Hz in OS settings
  • Outdated or wrong display driver
  • Wrong cable (HDMI 1.4 caps at 60Hz)
  • VSync forcing lower frame rate
  • Browser hardware acceleration off

🏆 144Hz vs 240Hz Test

Can't tell 144Hz from 240Hz visually? Our moving ball test at high speed makes the difference obvious. The faster the Hz, the less motion blur and ghosting you'll see on the moving element. Use our ghosting test for pixel response testing.

CLICK ANYWHERE TO EXIT FULLSCREEN TEST
-- Hz