Best route optimization APIs for field service

Q: Which optimization API should you choose to schedule field technicians?

Kardinal is the most complete solution for field technician scheduling, with 97% coverage of field service constraints. Solvice and LogisticsOS follow, tied at 78%, ahead of NextBillion AI (72%). The deciding criterion depends on your priority: real-time responsiveness, strict priority ranking, or synchronizing several technicians on the same appointment.

Q: Can you require the same technician to always serve the same customer?

Yes, this is called a continuity preference. Kardinal, Timefold, Solvice, GraphHopper, HERE and LogisticsOS offer it. Google covers it only partially, which remains a limitation for after-sales or contract maintenance operations where continuity matters.

Q: How do you handle urgent jobs in a field service schedule already set?

Real-time re-optimization automatically recalculates schedules during the day when an emergency comes in. Kardinal, Timefold, NextBillion AI and Solvice cover it in full. Other solutions require the dispatcher to step in manually.

Q: Can an optimization API synchronize two technicians on the same job?

Yes, but only one solution offers it today: Solvice. The constraint is useful for jobs that need two people at once, such as a heavy two-person installation or a visit requiring a doctor and a nurse at the same time.

Q: What is lexicographic optimization and why is it useful in field service?

Lexicographic optimization means setting an absolute hierarchy between objectives instead of combining them into a weighted formula. In field service, it lets you express: first meet every contractual appointment, then minimize travel time, then balance the load across technicians. The approach is more robust than classic weighting, which requires tedious calibration. Only Kardinal and HERE offer it.

Q: Which route optimization API should you use for home healthcare?

Home healthcare shares the constraints of field service, with a strong requirement for continuity between patient and caregiver. Kardinal, Solvice, HERE, GraphHopper, Timefold and LogisticsOS cover this continuity preference. Entry-level solutions such as Routific or Verso remain unsuited to this regulated context.

Kardinal

3 hours ago

In brief

APIs compared in this sector

97%

field service constraints covered by Kardinal, 1st in the ranking

78%

Solvice and LogisticsOS, tied behind

Among route optimization APIs for field services, Kardinal leads this sector ranking by a wide margin. One detail stands out: Kardinal is the only one of the eleven solutions able to interrupt an ongoing job for a mandatory break, a constraint no competitor models today.

Premium > 70%Kardinal (97%), Solvice (78%), LogisticsOS (78%), NextBillion AI (72%), Google (71%), HERE (71%).

Standard 50-70%Timefold (54%), GraphHopper (54%).

Basic < 50%Verso (46%), Routific (43%), Mapbox (29%).

Scheduling field technician jobs is a fundamentally different problem from parcel delivery. Complexity does not come from stop density but from the richness of the assignment constraints: the right technician, with the right skill, at the right time, in their own territory. Modeled poorly, that reality produces schedules that are theoretically optimal and impossible to run.

This article compares eleven route optimization APIs (Kardinal, Solvice, LogisticsOS, NextBillion AI, Google, HERE, Timefold, GraphHopper, Verso, Routific, Mapbox) on their ability to handle the specific constraints of field service operations: maintenance, after-sales, telecom, energy, inspections, home healthcare.

A sector analysis, drawn from the full benchmark

For a market-wide view across every solution and every sector: the main guide to route optimization APIs. The raw data sits in the 2026 benchmark.

Key takeaways

In this sector, Kardinal covers 97% of the relevant constraints. Solvice and LogisticsOS follow, tied at 78%, ahead of NextBillion AI (72%), then Google and HERE, also tied (71%).

Kardinal is the only solution in the panel that allows a mandatory break in the middle of an ongoing job: the other ten do not cover this constraint.

Synchronizing two technicians on the same appointment, useful for two-person jobs, is available only from Solvice.

Lexicographic optimization, which ranks objectives instead of weighting them, is available only from Kardinal and HERE.

What makes field services genuinely complex

Assignment is the heart of the problem

In parcel delivery, any driver can in theory make any delivery. In field service, that is almost never true. Every job requires specific technical skills, and a technician sent to a job they are not qualified for means a wasted trip at best and a liability issue at worst. The skill constraint is not a functional detail: it is the central constraint the whole schedule is built around.

The customer appointment is a contractual constraint

Unlike delivery, where the time slot is often indicative, the customer appointment in field service is contractual. A technician who misses the agreed window causes immediate dissatisfaction and sometimes contractual penalties.

Job duration varies

In delivery, service time at each stop is stable. In field service, a job can run from 30 minutes to several hours, and that duration often depends on the fault found on site or on the technician sent. Poor duration estimates throw the whole day's schedule off balance.

Territory and continuity preferences

Field service operators generally organize technicians by territory, a strong preference the optimizer should respect by default without turning it into a hard rule. On long-term maintenance contracts, sending the same technician to the same customer cuts ramp-up time and leverages the knowledge built up on that equipment.

Emergencies and re-optimization

Field service faces structural disruptions: urgent breakdowns to slot in, cancelled jobs, technicians held up longer than planned. The ability to re-optimize schedules during the day without rebuilding everything is a key productivity factor.

The critical constraints for a field service API

Three levels of requirement shape the market: the classic base that everyone covers, the intermediate constraints that separate the good from the average, and the advanced constraints that genuinely make the difference in the field.

Classic

Working time and technician count

The fundamental objectives of any job scheduling.

Covered by: All vendors except Mapbox.

Classic

Appointment windows

Covered everywhere, with widely varying levels of precision.

Covered by: All vendors.

Classic

Emergency prioritization

Ranking jobs as urgent, scheduled or discretionary.

Covered by: All vendors except Mapbox.

Classic

Spare part pickup

Collecting a part at a depot before heading to the customer.

Covered by: All vendors.

Intermediate

Minimize appointment lateness

Explicitly penalizing arrivals outside the contractual window.

Covered by: Kardinal, Solvice, LogisticsOS, Routific, Timefold, NextBillion AI and Google. Absent at GraphHopper, Mapbox and Verso.

Intermediate

Service time by technician

Adjusting job duration to the seniority of the technician assigned.

Covered by: Kardinal, Solvice, Google, HERE, Verso and LogisticsOS. Absent at Routific, Timefold, NextBillion AI and GraphHopper.

Intermediate

Workload balancing

Spreading working time fairly across the day.

Covered by: Kardinal, Routific, NextBillion AI, Solvice, GraphHopper and LogisticsOS. Absent at Timefold, Google, HERE, Mapbox and Verso.

Intermediate

Predictive traffic

Expected traffic is factored in before optimization, not corrected afterwards.

Covered by: Kardinal, NextBillion AI, Solvice, GraphHopper, Google, HERE and Mapbox. Absent at Routific, Timefold and Verso.

Advanced

Break allowed during service

Interrupting an ongoing job for a mandatory break, then resuming it.

Covered by: Kardinal only, out of the eleven solutions tested.

Advanced

Real-time re-optimization

Recalculating schedules when a technician runs late or an emergency comes in.

Covered by: Kardinal, Timefold, NextBillion AI and Solvice.

Advanced

Lexicographic optimization

Meeting every contractual appointment first, then minimizing travel.

Covered by: Kardinal and HERE only.

Advanced

Preferred technician or continuity

Favoring a senior on complex cases, or the one who usually handles the customer.

Covered by: Kardinal, Timefold, Solvice, GraphHopper, HERE and LogisticsOS. Partial at Google.

Advanced

Route compactness

Keeping each technician route geographically tight.

Covered by: Kardinal, Solvice and LogisticsOS only.

Advanced

Maximum distance from home base

Capping how far a technician can travel from their home or depot.

Covered by: Kardinal only in full. Partial at NextBillion AI, Solvice and LogisticsOS.

Advanced

Two-technician synchronization

For two-person jobs (electrician and crane operator, doctor and nurse).

Covered by: Solvice only, ahead of Kardinal included.

Field service API comparison

Kardinal

97% coverage · 1st/11

The most complete API for field jobs

Kardinal is the most complete solution for field service operations, with a particularly wide gap on advanced assignment constraints. It is the only vendor to combine real-time re-optimization, lexicographic optimization, maximum distance from home base and breaks allowed during service, the last of which no other vendor in the panel covers.

Its only real gap in this sector: synchronizing two technicians on the same appointment, available only from Solvice.

Best for

Telecom, energy and utility operators, industrial after-sales, maintenance on complex equipment fleets, any operation with long jobs or strong customer preferences.

Solvice

78% coverage · 2nd/11

One exclusive nobody else covers

Solvice shares second place with LogisticsOS. It covers route compactness alongside Kardinal, service time that depends on the technician, and the customer-technician continuity preference.

Its exclusive is absolute: it is the only solution in the panel, Kardinal included, to handle synchronizing two technicians on the same appointment.

Best for

Operators whose jobs require several people on site at once (complex installations, care requiring two professionals).

LogisticsOS

78% coverage · 2nd/11

Built around cost trade-offs

LogisticsOS finishes level with Solvice and covers the same advanced fundamentals: route compactness, service time by technician, continuity preference.

It stands out on cost modeling, notably guaranteed minimum revenue per assigned technician, level with Google, which matters to operators mixing employees and contractors.

Best for

Operators arbitrating between in-house technicians and subcontractors on economic grounds.

NextBillion AI

72% coverage · 4th/11

Solid on the fundamentals

NextBillion AI covers the fundamentals well: predictive traffic, real-time re-optimization, workload balancing across technicians. What it lacks is the finest field service layer: no technician-customer continuity preference, no service time by technician, no route compactness.

Best for

High-volume operators with moderate assignment constraints, particularly in Asian markets.

Google

71% coverage · 5th/11

Environmental reporting, no real time

Google covers CO₂ reporting per technician and guaranteed minimum revenue, but does not cover real-time re-optimization within this constraint scope, nor the technician-customer continuity preference beyond partial coverage.

Best for

Operations with a genuine environmental reporting requirement per job.

HERE

71% coverage · 5th/11

Strict priority ranking

HERE is the only solution besides Kardinal to offer lexicographic optimization, and it covers the continuity preference as well as service time by technician. Its weakness: real-time re-optimization is not covered.

Best for

Operators who want to rank their business priorities strictly without manual weighting.

Timefold

54% coverage · 7th/11

Strong responsiveness, narrow scope

Timefold fully covers real-time re-optimization and the technician continuity preference, two points where it joins Kardinal, but offers no predictive traffic and lags on the fundamentals.

Best for

Workforce-scheduling organizations that want strong responsiveness to disruptions across a narrower constraint scope.

GraphHopper

54% coverage · 7th/11

Open source foundation, flexible deployment

GraphHopper covers the continuity preference and workload balancing, but neither real-time re-optimization nor lexicographic optimization.

Best for

Operations with few advanced assignment constraints and a need for deployment flexibility (cloud or on-premise).

Verso, Routific and Mapbox

46% · 43% · 29%

Behind on professional field service

These three solutions are not built for the complexity of field service.

Verso (46%) stays limited to basic operations, without complete real-time re-optimization or continuity preference.
Routific (43%) covers some fundamentals (workload balancing, emergency prioritization) but lacks the advanced assignment capabilities.
Mapbox (29%) is not positioned for operational technician scheduling.

Summary table

Solution	Coverage	Break during job	Continuity	Real time	Lexicographic
Kardinal	97%	Full	Full	Full	Full
Solvice	78%	No	Full	Full	No
LogisticsOS	78%	No	Full	Partial	No
NextBillion AI	72%	No	No	Full	No
Google	71%	No	Partial	No	No
HERE	71%	No	Full	No	Full
Timefold	54%	No	Full	Full	No
GraphHopper	54%	No	Full	No	No
Verso	46%	No	No	Partial	No
Routific	43%	No	No	Partial	No
Mapbox	29%	No	No	No	No

Our verdict by operation size

Small operation · 3 to 8 technicians, simple jobs

Routific or Verso can be enough if your technicians have homogeneous profiles and appointments are flexible. Plan for a switch as your operation grows more complex.

Mid-size operation · 10 to 30 technicians, customer appointments

NextBillion AI if real-time responsiveness comes first, HERE if you need to rank business priorities without manual weighting, LogisticsOS if the economic trade-off between in-house technicians and subcontractors is central.

Advanced operation · 30+ technicians, frequent emergencies, team synchronization

Kardinal covers nearly the whole field. Solvice remains the only serious alternative if your jobs regularly require two technicians at once.

Test it on your real job schedules

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FAQ

Which optimization API should you choose to schedule field technicians?

Kardinal is the most complete solution for field technician scheduling, with 97% coverage of field service constraints. Solvice and LogisticsOS follow, tied at 78%, ahead of NextBillion AI (72%). The deciding criterion depends on your priority: real-time responsiveness, strict priority ranking, or synchronizing several technicians on the same appointment.

Can you require the same technician to always serve the same customer?

Yes, this is called a continuity preference. Kardinal, Timefold, Solvice, GraphHopper, HERE and LogisticsOS offer it. Google covers it only partially, which remains a limitation for after-sales or contract maintenance operations where continuity matters.

How do you handle urgent jobs in a field service schedule already set?

Real-time re-optimization automatically recalculates schedules during the day when an emergency comes in. Kardinal, Timefold, NextBillion AI and Solvice cover it in full. Other solutions require the dispatcher to step in manually.

Can an optimization API synchronize two technicians on the same job?

Yes, but only one solution offers it today: Solvice. The constraint is useful for jobs that need two people at once, such as a heavy two-person installation or a visit requiring a doctor and a nurse at the same time.

What is lexicographic optimization and why is it useful in field service?

Lexicographic optimization means setting an absolute hierarchy between objectives instead of combining them into a weighted formula. In field service, it lets you express: first meet every contractual appointment, then minimize travel time, then balance the load across technicians. The approach is more robust than classic weighting, which requires tedious calibration. Only Kardinal and HERE offer it.

Which route optimization API should you use for home healthcare?

Home healthcare shares the constraints of field service, with a strong requirement for continuity between patient and caregiver. Kardinal, Solvice, HERE, GraphHopper, Timefold and LogisticsOS cover this continuity preference. Entry-level solutions such as Routific or Verso remain unsuited to this regulated context.