Cable identification app
A cable identification app tells you which fiber is which inside an open cable, in the field, with no signal. The ones worth carrying do three things: forward lookup, so you enter a fiber number and get its buffer tube color and fiber color; reverse lookup, so you pick the colors in front of you and get the fiber number; and both of those fully offline. AllFiber's Fiber Optic Color Code Lookup does that across 7 international color standards and 199 cable configurations, with 98,898 pre-computed lookups sitting on the phone. No bars needed, no account to start.
Last updated: September 2026
Cable identification has gotten unnecessarily complicated. Strip it back and there are only two or three things a splice tech actually needs from an app: the right answer, in seconds, with gloves on and no service. Everything past that is software looking for a job.
Three things, and everything else is noise
Think about where the question actually gets asked. You are in a manhole or a vault, over an opened cable sheath, and the splice closure has to be buttoned back up before the crew rolls. The question is never abstract. It is "which buffer tube is fiber 47 in," or "I am holding a blue tube with a rose fiber, what number is that."
Get it wrong and you did not make a small mistake. You put a customer on the wrong strand, and somebody finds out when their service drops. Then it is a truck roll, a second trip into the same vault, and a conversation nobody enjoys. That is what a cable identification app is really being measured against, not "saves time." So the list is short: answer in both directions, work with zero signal, and stay usable with cold, gloved hands in bad light.
Forward lookup is the easy half
Every paper chart handles forward lookup. Fiber 47, TIA-598-C, twelve-fiber tubes, count it out and you land on the tube and the color. Slow, but it works, right up until the chart goes in standing water.
Reverse lookup is the half paper cannot do. You are looking at a tube color and a fiber color, sometimes with a tracer stripe, and you need the fiber number. On paper that means reading a grid backwards and counting again. The app treats it as a direct selection instead: pick the tube color you see, pick the fiber color you see, get the number. That is the lookup that comes up most often once a closure is open, and it is the one most references skip entirely.
Nothing is being calculated on your phone either. All 98,898 lookups are pre-computed and bundled with the app, so there is no math step to get wrong at 2am. Mental math on a 144-count cable is where errors come from, and taking the math out takes the error out with it.
Offline is the reason it exists
Most fiber reference websites are useless underground. There is no signal in a manhole, usually none in a vault, frequently none in an OSP pedestal on a rural route, and definitely none behind concrete.
So the lookup data ships inside the app as a bundled database. It does not phone home, it does not fetch a chart, it does not fall back to a spinner when the bars disappear. That is not a feature bullet, it is the entire point of the build. The fiber color code lookup app guide walks through what offline has to mean in practice.
One chart does not fit every cable
This is where a single printed TIA-598 sheet quietly fails you. The base color sequence is standard. The tube layout is not always what a generic chart implies, because manufacturers build their cables their own way, and a loose tube design, a ribbon cable, and a central tube cable do not present the same way when you open them up.
That is why the app carries 199 cable configurations instead of one chart. Some of those are manufacturer-specific tube layouts for Corning, CommScope, Prysmian, AFL, OFS/Furukawa and Sumitomo. The rest are generic standards layouts for everything else you run into. Sitting above that are 7 international color standards: TIA-598-C, IEC 60304, DIN VDE 0888, S12, FIN2012, IEC 60794-2 and Type E.
There is also an interactive cable cross-section diagram with manufacturer-accurate tube positioning. You tap the tube you are actually looking at rather than translating a flat grid into a physical bundle in your hand. For a new tech, that one screen answers most of what they would otherwise be asking a senior tech over the radio. The fiber identification tool guide goes deeper there.
The details that only show up in the field
Dark theme, because a white screen in a manhole at night wrecks your night vision and you still have hours of work left. Large tap targets, because nobody is peeling off a glove in February to hit a tiny button. Both sound cosmetic until you have tried the alternative on a cold night.
Colorblind techs have a harder version of this whole problem, slate against white especially. Being able to work from the tube position and the fiber number, rather than depending entirely on telling two close colors apart by eye, takes some of that off.
What it costs
24 hours free with full access to everything in the app, and no account required to start. After that it is a single $4.99 one-time purchase. Nothing recurring, no tiers to compare. You buy it once and it is yours.
One thing worth being precise about, because it comes up: Fusion Splicer Error Codes, the fusion splicer error code app from AllFiber, is a separate app with its own separate $4.99 purchase. It is not part of the Color Code purchase, and buying one does not give you the other.
To look at the reference itself before installing anything, the Fiber Optic Color Code Lookup page has it.
Frequently asked questions
What is a cable identification app?
It is a tool that tells you which fiber is which inside a multi-fiber cable. Give it a fiber number and it returns the buffer tube color and fiber color; give it the colors you can see and it returns the fiber number. The useful ones also carry manufacturer tube layouts, not just a single generic color chart.
Does a cable identification app work without cell signal?
It has to, or it is not a field tool. Fiber Optic Color Code Lookup keeps all 98,898 lookups in a database bundled inside the app, so it runs the same in a manhole, a vault, or an OSP pedestal with zero bars. There is no fetch, no sync step, and no degraded mode when service drops. That offline requirement is the whole premise behind any fiber optic technician app worth carrying, and the first check on our best app for fiber techs list.
Can I look up a fiber number from the colors I can see?
Yes, that is reverse lookup. Select the tube color and the fiber color in front of you and the app returns the fiber number. It is the direction paper charts cannot handle without counting backwards through a grid, and it is the direction that comes up most once a splice closure is already open.
Does one color chart cover every manufacturer?
No, and that assumption causes real mis-identifications. Tube layouts differ between manufacturers, and loose tube, ribbon, and central tube cables each present differently. The app carries 199 cable configurations for that reason, covering manufacturer-specific layouts from Corning, CommScope, Prysmian, AFL, OFS/Furukawa and Sumitomo alongside generic standards layouts.
Is it a subscription?
No. You get 24 hours free with full access and no account needed to begin, then a single $4.99 one-time purchase. There is no recurring charge and no higher tier inside the app. Fusion Splicer Error Codes is a separate app from AllFiber with its own separate $4.99 purchase.
The short version
Two or three things done properly beats twenty done halfway. Answer in both directions, work with no signal, survive gloves and bad light. That is the whole list, and it is short enough that there is no excuse for missing it.