Here's a pipe solution:

strong-number.pipe.ts:

@Pipe({name: 'strongifyNumber'}) export class StrongifyNumber implements PipeTransform { transform(value: string): string { let values: string[] = value.split(' ') if(values.length == 2){ return ' <b>'+values[0]+'</b> ' + values[1]; } return value; } } 

app.module.ts:

import { StrongifyNumber } from './strong-number.pipe'; @NgModule({ declarations: [ AppComponent, StrongifyNumber ], imports: [ BrowserModule, FormsModule ], providers: [StrongifyNumber], bootstrap: [AppComponent] }) 

template:

<span [innerHTML]="test | strongifyNumber"></span> 

Here's a pipe solution:

strong-number.pipe.ts:

@Pipe({name: 'strongifyNumber'}) export class StrongifyNumber implements PipeTransform { transform(value: string): string { let values: string[] = value.split(' ') if(values.length == 2){ return ' <b>'+values[0]+'</b> ' + values[1]; } return value; } } 

app.module.ts:

import { StrongifyNumber } from './strong-number.pipe'; @NgModule({ declarations: [ AppComponent, StrongifyNumber ], imports: [ BrowserModule, FormsModule ], providers: [StrongifyNumber], bootstrap: [AppComponent] }) 

template:

<span [innerHTML]="list.members | strongifyNumber"></span>