Ask HN: Best service to translate an SPA?

The last time my team had to do this we fired off a spreadsheet with the keys, English text, and an empty column for the translation to a translation service, and then loaded the result into the i18n lib we were using at the time. But we later got feedback from native speaking users that the context of the translation was sometimes incorrect or could have been better.

I feel like it would have helped the translator if they could see the text in the actual application to aid them with the context.

Have things improved since last time?