About frame rate and frame time
Frame rate and frame time describe the same thing from two angles. Frame rate, measured in frames per second (FPS), counts how many complete images a display renders each second. Frame time, measured in milliseconds (ms), is how long a single frame takes to draw. They are reciprocals: a high frame rate means a short frame time, and a smooth-looking game depends on the frame time staying consistently short, not just averaging well.
This converter lets you type either value and read the other instantly. Enter 60 in the FPS field and it shows 16.67 ms. Enter 6.94 ms and it shows about 144 FPS. The breakdown panel also gives microseconds per frame and a qualitative note, because the practical meaning of a number changes across the range: 30 FPS feels cinematic but slightly choppy in fast motion, 60 FPS is the long-standing console and TV baseline, 120 to 144 FPS is the modern high-refresh desktop sweet spot, and 240 FPS and beyond is competitive esports territory.
Why frame time matters more than the headline average: a game can report 120 FPS average while still stuttering, because one slow 50 ms frame buried among many fast ones barely dents the average but is plainly visible as a hitch. Reviewers therefore quote 1 percent and 0.1 percent low figures, which capture the worst frames. Converting those lows to frame time often explains a stutter that the average FPS number hides.
How it works: the formula
One second is 1000 milliseconds, so dividing 1000 by the frame rate gives the time budget for each frame. The relationship inverts cleanly in both directions.
frame time (ms) = 1000 / frame rate (FPS) frame rate (FPS) = 1000 / frame time (ms) microseconds per frame = frame time (ms) x 1000
- 1000 is the number of milliseconds in one second; it is the constant that links the two units.
- Frame time is the budget your hardware has to finish a frame. To hold 60 FPS, the CPU and GPU together must finish every frame inside 16.67 ms.
- The relationship is nonlinear. Going from 30 to 60 FPS halves frame time (33.3 to 16.7 ms, a 16.6 ms saving), but going from 120 to 240 FPS only saves 4.2 ms. Each extra FPS buys less time at the top end.
Worked example
Suppose a benchmark reports an average of 90 FPS but a 1 percent low of 45 FPS. What does that mean in frame-time terms?
- Average frame time: 1000 / 90 = 11.1 ms. Typical frames are comfortable.
- 1 percent low frame time: 1000 / 45 = 22.2 ms. The worst frames take twice as long.
- The gap: 22.2 minus 11.1 = 11.1 ms of variance between a good frame and a bad one.
- Perceived effect: a jump from 11 ms to 22 ms once or twice a second reads as a visible hitch, even though 90 FPS sounds smooth.
Reference table: common frame rates
Frame time and context for the rates you meet most often.
| Frame rate | Frame time | Typical use |
|---|---|---|
| 24 FPS | 41.67 ms | Cinema film standard |
| 30 FPS | 33.33 ms | Older consoles, mobile, video |
| 60 FPS | 16.67 ms | Console and desktop baseline |
| 120 FPS | 8.33 ms | High-refresh gaming |
| 144 FPS | 6.94 ms | Common gaming monitor refresh |
| 240 FPS | 4.17 ms | Competitive esports |
| 360 FPS | 2.78 ms | Elite-tier esports displays |
Common pitfalls
- Chasing average FPS over consistency. A steady 60 FPS feels smoother than a jittery 90 FPS average that dips to 30. Watch the 1 percent lows and the frame-time graph, not just the big number.
- Confusing frame rate with refresh rate. Frame rate is how many frames the game produces; refresh rate (Hz) is how many times the monitor updates. A 144 Hz panel cannot show more than 144 distinct frames per second no matter how high the FPS climbs.
- Ignoring screen tearing. When frame rate and refresh rate are not synchronised, frames split across a refresh and tear. V-Sync, G-Sync, or FreeSync align them, at some latency or frame-rate cost.
- Assuming higher is always better. Above your monitor's refresh rate, extra frames are discarded, though they can still slightly reduce input latency. Past that, the gains are marginal.
- Forgetting input latency. Frame time is only part of the total delay from input to photons on screen. Display processing, render queue depth, and USB polling all add milliseconds.
Frequently asked questions
What is the difference between frame rate and frame time?
They measure the same thing inversely. Frame rate (FPS) counts frames per second; frame time (ms) is how long one frame takes. At 60 FPS each frame takes 16.67 ms. Frame time is often the more useful figure for diagnosing smoothness, because a single long frame shows up clearly in milliseconds but barely moves the average FPS.
Why does 60 FPS equal 16.67 ms?
Because there are 1000 milliseconds in one second, and dividing those 1000 ms across 60 frames gives 1000 / 60 = 16.67 ms per frame. The same arithmetic produces 8.33 ms at 120 FPS and 6.94 ms at 144 FPS. The frame time is simply how much of each second is allotted to one frame.
Are 1 percent lows more important than average FPS?
For perceived smoothness, usually yes. The 1 percent and 0.1 percent low figures capture the slowest frames, which are exactly the ones a player notices as stutter. A high average with poor lows feels worse than a slightly lower average that stays consistent. Converting the lows to frame time exposes variance the average hides.
Does frame rate need to match my monitor's refresh rate?
Ideally they are aligned. A 144 Hz monitor can display at most 144 unique frames per second; frames beyond that are discarded. If frame rate and refresh rate drift out of sync you get tearing, which V-Sync, G-Sync, or FreeSync fixes by matching the two. Running FPS above the refresh rate can still trim input latency slightly.
Is 30 FPS playable?
Yes, and it has been the standard for many console titles and most film and video. At 33.33 ms per frame it looks cinematic but can feel slightly sluggish in fast-paced shooters or racing games, where 60 FPS or higher gives crisper response. Whether 30 FPS is acceptable depends on the genre and your sensitivity to motion.