Speedrun Timer Online — Splits, Personal Best & Stream Overlay

An online speedrun timer with splits and personal-best comparison

This speedrun timer runs in your browser with nothing to install. Name your splits, press Space to start and to split, and every split is compared with your personal best: green when you are ahead, red when you are behind, gold when a segment is the fastest you have ever done it. Sum of best and best possible time update as you play, and a finished run that beats your PB is saved as the new one.

For streams there is an overlay mode: a compact timer on a chroma-green, magenta or black background that OBS or any streaming software can key out from a window capture, or full screen on a second monitor. Splits are stored in this browser and can be exported as JSON or imported from a .lss split file.

How to use the Speedrun Split Timer

1. Open Edit splits, enter the game, category and one split name per line, and press Save splits (or import a .json or .lss file).
2. Press Start or the Space bar when the run begins.
3. Press Space at the end of each segment. Backspace undoes a split, S skips one, P pauses and R resets.
4. Watch the +/− column, the previous-segment delta, sum of best and best possible time.
5. For streaming, tick Overlay mode, choose a chroma background and capture the window — or go full screen.

Speedrun Split Timer features

How splits, golds and sum of best work

A split is the run time when you finish a segment; a segment time is split minus the previous split. The +/− column compares your split with the personal-best split at the same point, so −2.80 means you are 2.8 seconds ahead of your PB run there. A gold split is a segment faster than your best ever segment, whatever the rest of the run did.

Sum of best adds up your best segments: with golds of 1:02.10, 2:01.30, 3:20.00, 2:15.00 and 1:24.00 it is 10:02.40 — the run you would get by playing every segment at your best. Best possible time is your current split plus the sum of best of the segments still to come, so it tells you mid-run whether a PB is still on.

Example: against a 10:30.00 PB you split the first segment at 1:00.00 (−5.20 and a gold), lose time in the second (+2.20), skip a split you missed, recover to −2.55 and finish in 10:20.00. That run becomes your PB, two segments become golds and the sum of best drops to 9:56.30.

Using it as an OBS overlay

• Tick Overlay mode and choose Chroma green. In OBS, add a Window Capture of the browser window, then a Chroma Key filter (green). Crop to the timer.
• Or press Full screen on a second monitor and capture that display.
• Hotkeys only work while this browser tab has keyboard focus — with the game focused, use a second device, a macro key that focuses the browser, or click the Split button.
• Timing uses the browser’s high-resolution clock (performance.now), shown to the hundredth of a second. A paused or background tab keeps counting correctly; reloading the page ends the run.

Speedrun timer vs a stopwatch

A stopwatch records laps; a split timer knows the route in advance, compares each split with your best and remembers golds. For frame-perfect tricks, the frame time calculator converts frames to milliseconds, and the input lag test measures your setup’s delay.