HiveCode/time

HH:MM:SS → hours, minutes, seconds.

A precise duration converter. Type a duration; read the equivalent in hours, minutes, and seconds. Free, no sign-up, runs in your browser.

Result
Accepts HH:MM:SS, MM:SS, or plain seconds. Negative values supported.
  • 1.5125 hours
  • 90.75 minutes
  • 5,445 seconds
Reference
Input Meaning In seconds
one minute 60
half hour 1,800
one hour 3,600
two and a half hours 9,000
one day 86,400
How it works

How HH:MM:SS conversion works

HH:MM:SS is a sexagesimal format: hours, minutes, and seconds counted in base 60. Converting it to a single unit means flattening that base into a single quantity. The math is simple, but the small details — rounding, leading zeros, values past 24 hours — are where most converters get sloppy.

Formula

total_seconds = hours × 3600 + minutes × 60 + seconds
total_minutes = hours × 60 + minutes + seconds ÷ 60
total_hours = hours + minutes ÷ 60 + seconds ÷ 3600

Rounding

Decimal outputs are shown with up to four decimal places. Trailing zeros are trimmed. We round half-to-even (banker’s rounding) to avoid bias when chaining conversions — the same rule used by IEEE 754. For most invoicing and scheduling, two decimals are plenty; the extra precision is there when you need it.

Edge cases

  • Durations beyond 24 hours are valid. 36:00:00 means 36 hours, not 12:00:00 the next day. The tool treats input as a duration, not a clock time.
  • Two-segment input like 5:30 is read as MM:SS (five minutes thirty seconds), not HH:MM. To enter five hours thirty minutes, type 5:30:00.
  • Negative durations are supported. Useful for time deltas where one event precedes another. The sign propagates through every output.
  • Plain integers are treated as seconds. 90 becomes 0:01:30. Decimal seconds are accepted: 1.5 means one and a half seconds.
When to use it

When you actually need this conversion

Most fields that touch time professionally use HH:MM:SS for human reading and decimal units for math. The translation between them is where mistakes happen — usually on a Sunday night closing the books, or at 2 AM rendering a final cut.

Timesheets, invoicing and payroll
Hours are billed and paid in decimal: 2.5 hours, not 2:30:00. A timesheet entry of 1h 45m 30s becomes 1.7583 hours. Multiply by the rate and you have the line item. The slip-up is usually mental arithmetic — 45 minutes is 0.75, not 0.45 — and it compounds across a month of entries. Converting at entry time, not at month-end, is the cheap fix.
Video and post-production
Editing software speaks SMPTE timecode (HH:MM:SS:FF) but rendering, DRM packaging, HLS/DASH segmentation, and ffmpeg flags often want seconds. A cut at 00:01:23:12 on a 24 fps timeline is 83.5 seconds. Frame-accurate trimming, chapter markers in YouTube descriptions, and FFmpeg cue points all rely on the seconds representation. Decimal minutes are useful when planning a runtime budget across multiple scenes.
Audio, broadcasting and podcasting
Podcast chapter markers (Podcasting 2.0, ID3v2) accept either HH:MM:SS or seconds depending on the host. DAW automation curves and audio loop calculations work in samples (seconds × sample rate). For a 44.1 kHz mix, a 3-minute 14-second segment is 8,555,400 samples. Going through the seconds representation is the only sane intermediate step.
Sports, training and research
Lap splits, interval training, race timing, and any kind of time-series analysis live in seconds for arithmetic and in HH:MM:SS for reporting. Converting a marathon time of 3:45:22 into 13,522 seconds lets you compute pace, percentages, and deltas without rebuilding sexagesimal arithmetic each time.
Worked examples

Conversions with context

A handful of realistic inputs and what they translate to. Skim the scenario column to find the one that looks like your problem; the numbers do the rest.

  1. 01:30:45

    Billable consultation, 1h 30m 45s logged

    1.5125 hours · 90.75 minutes · 5,445 seconds

    At $80/hour the invoice line is $121.00.

  2. 00:14:30

    Podcast intro segment

    0.2417 hours · 14.5 minutes · 870 seconds

    Chapter marker for ID3v2 or PodLove uses 870.

  3. 00:00:12.5

    Video cut on a 24 fps timeline

    0.0035 hours · 0.2083 minutes · 12.5 seconds

    12.5 s × 24 fps = 300 frames. Frame-accurate.

  4. 03:45:22

    Marathon finish time

    3.7561 hours · 225.3667 minutes · 13,522 seconds

    13,522 ÷ 26.2188 = 515.7 s/mile pace.

  5. 36:00:00

    Overtime shift across two calendar days

    36 hours · 2,160 minutes · 129,600 seconds

    Stays a duration; not interpreted as 12:00 next day.

  6. 00:00:90

    Quick-typed entry, 90 seconds total

    0.025 hours · 1.5 minutes · 90 seconds

    Seconds field >59 is normalised, not rejected.

  7. 02:30:00

    Half-day workshop

    2.5 hours · 150 minutes · 9,000 seconds

    Round decimal hour — the easy case.

  8. 24:00:00

    One full day

    24 hours · 1,440 minutes · 86,400 seconds

    86,400 seconds is the canonical day length.

About

About this tool

Built for video editors marking cuts, athletes splitting laps, podcasters logging timecodes, developers handling ISO 8601 durations, and anyone tired of opening the calculator to multiply by 3600. The math is trivial; the friction was the problem.

Questions
How do I convert HH:MM:SS to seconds?

Multiply hours by 3600, minutes by 60, and add the seconds. Example: 01:30:45 = 3600 + 1800 + 45 = 5,445 seconds.

How do I convert HH:MM:SS to minutes?

Multiply hours by 60, add minutes, then add seconds divided by 60. Example: 01:30:45 = 60 + 30 + 0.75 = 90.75 minutes.

How do I convert HH:MM:SS to decimal hours?

Divide minutes by 60 and seconds by 3600, then add to hours. Example: 01:30:45 = 1 + 0.5 + 0.0125 = 1.5125 hours. Most timesheet and payroll systems expect this format.

Can the input be longer than 24 hours?

Yes. The converter treats input as a duration, not a clock time, so 48:00:00 means forty-eight hours — useful for project totals, overtime, or long recordings.

Why does my result have so many decimal places?

Decimal outputs show up to four decimal places to keep precision useful when chaining conversions. For invoicing and scheduling two decimals are enough; the extra are there if you need them. Trailing zeros are trimmed automatically.

Does this run offline?

Yes. The conversion runs entirely in your browser with plain JavaScript. Nothing is sent to a server, no values are logged.

Who made it?

HiveCode. Same small team behind a handful of other focused tools at hivecode.cloud.